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Abstract

We examined how juvenile defendant psychosocial maturity, age, and gender influence mock jurors’ perceptions. Jury-eligible participants (N = 1,850) ages 18 to 73 (M = 27.81, SD = 11.47) were recruited from Amazon Mechanical Turk (n = 994) and a college campus (n = 858). Participants acted as mock jurors and were randomly assigned to an experimental condition manipulating defendant psychosocial maturity, age, and gender. After reading case vignettes and expert testimony about the defendant’s psychosocial maturity, participants reported their perceptions of the defendant’s responsibility for the crime, guilt, and appropriate sentencing. Participants perceived less mature adolescents as less responsible for criminal behavior and were less likely to find them guilty, irrespective of age. Jurors viewed girls more harshly than boys.

Keywords

juvenile delinquency juvenile justice sentencing jury decision making psychosocial maturity

Both psychological research (Cauffman & Steinberg, 2000) and legal precedent (Miller v. Alabama, 2012; Roper v. Simmons, 2005) assert that adolescents are less responsible for criminal behavior than adults on account of their diminished psychosocial maturity (Steinberg, 2013). Although adolescents are afforded legal protections in the justice system because of their still-developing maturity, psychosocial development is an internal process that is related to, yet distinct from one’s chronological age (Greenberger & Sørenson, 1974), and may not be discernable to legal actors such as attorneys, judges, and jurors using visual cues alone (Scott et al., 2006). Further, we speculate that jurors and judges may not fully appreciate the influence of maturity on culpability or be able to accurately discern the maturity of specific individuals, which could negatively affect verdicts and sentencing decisions in cases involving juvenile defendants. Additionally, it is unclear how gender and age might interact with psychosocial maturity to influence legal outcomes for juveniles. The present study seeks to examine how information about adolescent defendants’ age, gender, and psychosocial maturity influences mock juror perceptions of culpability, guilt, and sentencing recommendations.

Juvenile Psychosocial Maturity and Legal Culpability

Adolescence is often described by psychological researchers as the period of life beginning with puberty and ending with the attainment of adult roles and responsibilities (Robards & Bennett, 2013). It is noteworthy that this definition is not tied to a specific chronological age (unlike the legal definition, which cuts off adolescence at age 18 years); highlighting the distinction between one’s biological maturity and psychological maturity. Psychosocial maturity reflects capacities for responsibility, perspective, and temperance. Responsibility refers to self-reliance, identity, and independence; perspective encompasses the ability to consider situations from different viewpoints and within a broader context; and temperance indicates the ability to limit impulsivity and evaluate situations before acting (Cauffman & Steinberg, 2000). By age 16, most adolescents have reached a level of cognitive maturity in which they are able to engage in decision-making similar to that of adults under “ideal” circumstances (i.e., in which they are provided with relevant information, have opportunities to consult with an adult, and are not experiencing social pressures or time constraints; Steinberg & Cauffman, 1996; Steinberg, Graham, et al., 2009). However, adolescents’ capacities for responsibility, perspective, and temperance are still developing through their mid-20s (Icenogle et al., 2019; Steinberg, Cauffman, et al., 2009). Adolescents demonstrate increased impulsivity and diminished regard for future consequences when making stressful and time-sensitive decisions, and are influenced by social factors that do not similarly affect adults’ decision-making (e.g., peer pressure; Albert et al., 2013; Cauffman & Steinberg, 1995; Chein et al., 2011; Cohen et al., 2016; Gardner & Steinberg, 2005). Adolescents often make decisions in highly emotive situations, while subjected to peer pressure, and without ample time to contemplate future consequences—in fact, this is kind of context that adolescents often find themselves in when faced with the decision to engage in risky or delinquent behaviors.

Due to the recognition that adolescents’ decision-making is negatively affected by their psychosocial immaturity—particularly when engaging in delinquent behavior—adolescents are considered less criminally responsible than adults (Cauffman & Steinberg, 2000). The U.S. Supreme Court has established legal precedent to this effect by limiting the severity with which young offenders may be treated within the criminal justice system. For example, juveniles cannot be sentenced to death (Roper v. Simmons, 2005) or mandatory life without parole (Miller v. Alabama, 2012). Additionally, most cases involving adolescent defendants are processed in a separate juvenile court system, which is designed to capitalize on adolescents’ potential for rehabilitation (Sickmund & Puzzanchera, 2014). Every court system in the U.S., however, includes mechanisms that allow transfer from juvenile court to criminal (adult) court for juveniles deemed particularly mature or for crimes deemed particularly serious. Unlike juvenile court—in which most cases are determined by a juvenile court judge—criminal court may allow juvenile defendants to face a jury (McKeiver v. Pennsylvania, 1971). Although jurors tend to attribute less responsibility to younger adolescent defendants (Ghetti & Redlich, 2001), age is merely a biological construct, with little bearing on culpability; whereas psychosocial maturity is a developmental construct more relevant to culpability (Cauffman & Steinberg, 2000). However, the role of adolescent psychosocial maturity on juror decision-making remains unclear.

Juror Legal Decision-making

Age

Despite the relative importance of psychosocial maturity over age in juvenile culpability, chronological age may be more immediately obvious to a juror and may be considered more heavily in jurors’ legal decisions. As would be expected, most research finds that mock jurors view younger adolescents (11–12\ years old) as less responsible for criminal behavior than older adolescents (16–17 years old) for both nonviolent and violent crimes (Bradley et al., 2012; Ghetti & Redlich, 2001; McPhetres & Hughes, 2016). However, leniency in culpability perceptions appears to have a limit; one study found that mock jurors perceived a 15-year-old and a 20-year-old as equally responsible for armed robbery (Scott et al., 2006). These results indicate that mock jurors tend to attribute less responsibility to younger adolescents as compared to older adolescents, but the mitigating effect of age on responsibility may disappear once an adolescent is old enough to be perceived as an adult.

Although mock jurors tend to view younger adolescents as less criminally responsible than older adolescents, these attributions do not always translate to actual verdicts. Some research indicates that younger adolescents are not only seen as less blameworthy than older adolescents, but are also less likely to be found guilty by mock jurors for nonviolent and violent crimes (Katzman et al., 2022; McPhetres & Hughes, 2016; Pozzulo et al., 2015; Semple & Woody, 2011; Tang & Nunez, 2003). Other research, however, finds no difference in mock jurors’ guilty verdicts between younger adolescents, older adolescents, and young adults for a variety of violent crimes (Walker & Woody, 2011; D. Warling & Peterson-Badali, 2003). Research is therefore mixed regarding the effect of juvenile age on guilty verdicts.

Existing research is also mixed regarding the influence of juvenile age on sentencing. In mock juror research, younger adolescents are given less severe sentences as compared to older adolescents and young adults (Walker & Woody, 2011; D. Warling & Peterson-Badali, 2003). Additionally, mock jurors report feeling that judges should take a juvenile defendant’s age into account during sentencing—particularly for younger adolescents (Bradley et al., 2012). In research using actual juvenile dispositions as outcomes (as opposed to mock cases), however, younger adolescents appear to receive more severe sanctions than both older adolescents and young adults (Cauffman et al., 2007; Kurlychek & Johnson, 2004). For example, Cauffman et al. (2007) examined court dispositions in a sample of 14 to 18-year-old serious juvenile offenders and find a 0.805 odds ratio for age (measured continuously) and court disposition, such that older adolescents are less likely to receive a disposition to a secure placement (compared to probation) than younger adolescents. Other research suggests that age does not play a role in sentencing severity one way or another; instead, legally relevant factors such as the type of crime, violence during the offense, and prior offenses are more significant predictors of sentencing severity (Cauffman et al., 2007; Ghetti & Redlich, 2001). These legal factors may therefore overshadow any potential effects of age on sentencing decisions. Taken together, this research suggests that age may differentially influence perceptions of culpability, guilty verdicts, and sentencing decisions.

Developmental Maturity

Though chronological age is one possible tool for inferring one’s developmental stage, it is not necessarily the best indicator of one’s development considering there is wide variability in timing of developmental maturity. However, the research examining how defendant developmental maturity affects jury decision making is relatively scant compared to that of chronological age. Some research examining jurors’ perspectives of defendants with developmental delays indicates that mock jurors are less likely to find such defendants guilty and view them as less responsible for their crimes compared to defendants without a delay (Najdowski et al., 2009). A few studies have explored mock jurors’ perspectives of guilt based on defendants’ developmental age. For example, research by Pica et al. (2017) found that mock jurors were less likely to rate defendants who were described as developmentally younger (e.g., “developmentally 14-years-old”) as guilty, compared to defendants who were described as developmentally older (e.g., “developmentally 24-years-old”). Interestingly, when information on defendants’ chronological age and developmental age are provided, mock jurors were more likely to provide lower ratings of guilt for older defendants (i.e., 24 years old) with developmental delays (i.e., developmentally 14 years old) compared to the typically developing 24-year-old defendant (Pica et al., 2017). Although this body of work focuses more on intellectual disabilities and developmental delays that are cognitive in nature (which are distinct from individual differences in psychosocial maturity—the focus of the present study), it has relevance to discussions of developmental maturity, as both have been shown to affect culpability. It provides a useful lens for considering how psychosocial maturity more specifically may also affect jurors’ perceptions of defendants.

Despite the important implications of developmental maturity on adolescent behavior, research regarding the impact of adolescent maturity on juror decision-making is limited. One such study manipulated maturity by having participants read a clinician’s notes that described a juvenile defendant as either able or unable to exhibit self-control, consider consequences, and weigh risks and benefits, and either not or highly influenced by others (McPhetres & Hughes, 2016). The results of this study suggested that mock jurors view less mature juveniles as less responsible for both property and violent crimes compared to more mature juveniles. A second study found that when mock jurors were provided with information about specific maturity deficits (i.e., impulsivity, future orientation, or reward bias), they perceived juvenile defendants as less responsible for criminal behavior than when they were not provided with any maturity information (Hughes & McPhetres, 2016). Although limited, these two studies suggest that mock jurors would consider psychosocial maturity (if such information was provided) when evaluating the culpability of juvenile defendants.

Beyond perceptions of responsibility, the relationship between adolescents’ psychosocial maturity and juror decision-making (i.e., guilty verdicts) is also ambiguous. In the only known study to examine this relationship, McPhetres and Hughes (2016) found that mock jurors were less likely to give a guilty verdict to a juvenile who used drugs when they were depicted as less mature. Maturity did not, however, influence guilty verdicts for juveniles who were abuse victims. However, this study did not include a control condition in which mock jurors did not receive any information regarding adolescent maturity, so it remains unclear how jurors would have rated defendant guilt without any maturity information provided. Juvenile maturity might influence mock juror determinations of guilt under certain circumstances. Yet, aspects of the case and the juvenile’s history may be more significant.

Research regarding the influence of juvenile psychosocial maturity on sentencing/disposition outcomes is mixed. In mock juror research, longer sentences were recommended for juveniles whom the jurors perceived to be more mature (Walker & Woody, 2011). However, this association was based on jurors’ perceptions of juvenile maturity, which may or may not be accurate reflections of a juvenile’s true maturity. Additionally, crime severity was a stronger predictor of sentencing decisions than jurors’ maturity perceptions. In examinations of actual juvenile dispositions—which are typically decided by judges rather than jurors—adolescent maturity is not associated with disposition outcomes for younger or older juveniles (Cauffman et al., 2007). The researchers in this study hypothesized that the lack of a relation between maturity and disposition may have been due to differences in judicial perceptions; some judges may view developmental immaturity as a mitigating factor, making juveniles less responsible for their actions, while other judges may view developmental immaturity as an aggravating factor, making juveniles more likely to reoffend. Furthermore, information about juvenile maturity may have a different influence on jurors than judges.

Importantly, in the absence of maturity information, mock jurors do not seem to recognize differences in juvenile maturity. One study presented mock jurors with photos of mock juvenile offenders of various ages and found that mock jurors did not perceive differences in psychosocial maturity between offenders identified as 12 years old and 15 years old; they did, however, rate the 15-year-old as more criminally responsible than the 12-year-old (Scott et al., 2006). Mock jurors also attribute greater maturity to juveniles in cases resulting in more mild outcomes (i.e., injury) as compared to those resulting in more serious outcomes (i.e., death; Walker & Woody, 2011). These results may indicate that mock jurors attribute arbitrary maturity ratings to juveniles, relying on non-relevant case details such as age or crime severity to determine maturity, when specific maturity information is not provided.

Given that adolescent defendants would only face a jury trial if they were transferred to criminal court, experimental conditions examining this topic should reflect situations that would warrant juvenile transfer. Although adolescents as young as 10 years old may be eligible for transfer to adult court in some states, juveniles must be at least 13 years old in 24 states—and even then, transfer is often reserved for the most serious of crimes like murder (Office of Juvenile Justice and Delinquency Prevention, 2022). A 12-year-old charged with assault likely would not rise to the level of transfer in any state, and therefore would not see a jury. Additionally, few studies from the existing prior research on this topic have compared jurors’ perceptions when provided with psychosocial maturity information versus when no such information is provided. Including a no-information condition in research on how psychosocial maturity can influence perceptions is important given that most courts likely do not mention maturity in current practices and including any kind of maturity information would need to be compared to “business as usual.” The current study addresses both of these limitations of prior research.

Gender

Along with age, gender is another attribute of juvenile defendants that can influence jurors’ perceptions of responsibility, guilt, and sentencing. Girls have tended to be significantly less likely than boys to become involved with the justice system historically, although in recent years the gap between juvenile arrest rates for males and females has decreased (Development Services Group, 2023). Indeed, boys tend to be treated more harshly than girls throughout juvenile justice system processing. According to the Office of Juvenile Justice and Delinquency Prevention (2023), in 2021, males committed delinquency 2.6 times more than females (7.34 per 1,000 youth vs. males’ 19.37). Boys are more likely than girls to have their cases referred for formal processing rather than diversion at intake (Evangelist et al., 2017; Leiber, 2013; MacDonald & Chesney-Lind, 2001), receive a guilty adjudication (Spivak et al., 2014), be sentenced to secure correctional facilities at disposition (Cauffman et al., 2007; Espinosa et al., 2013; Tam et al., 2016). Although some studies suggest that gender does not influence adjudication (i.e., guilt; Blais & Forth, 2014; Freiburger & Burke, 2011) or disposition (i.e., sentencing; Spivak et al., 2014), and some suggest that girls may actually be treated more harshly than boys (Carr et al., 2008; MacDonald & Chesney-Lind, 2001; Teilmann & Landry, 1981), most prior research supports the notion that boys are treated more harshly than girls throughout justice system proceedings. Although prior research has examined interactions between gender and factors such as race, ethnicity, age, trauma, and crime severity, no known studies have experimentally examined the interaction between gender and psychosocial maturity.

The Present Study

Although psychosocial maturity is not immediately obvious to a jury, it is an essential factor to consider when discussing criminal culpability. Research examining the influence of juvenile psychosocial maturity on juror decision-making is sparse, and many are limited in terms of ecological validity and/or experimental methodology. The current study will address limitations of prior research by: (a) selecting vignettes with ages old enough and crimes serious enough to warrant juvenile transfer, (b) utilizing an experimental design with random assignment to conditions, and (c) including a control condition in which no information regarding adolescent maturity is included. Mock jurors’ perceptions of responsibility, guilt, and sentencing for a juvenile defendant charged with vehicular hit-and-run will be examined using a 4 (defendant psychosocial maturity: less than, equal to, or greater than peers, or control condition) × 3 (defendant age: 13, 15, 17) × 2 (defendant gender: male, female) experimental design. We hypothesized the following main effects:

1. Psychosocial Maturity: Mock juror ratings of responsibility, guilt, and sentencing severity will increase as the maturity of the defendant increases, and the control condition (i.e., no psychosocial maturity information provided) will be most similar to the more mature condition.

2. Age: Mock juror ratings of responsibility, guilt, and sentencing severity will increase as the age of the defendant increases.

3. Gender: Mock juror ratings of responsibility, guilt, and sentencing severity will be greater for male defendants than female defendants.

Additionally, all two- and three-way interactions between age, gender, and maturity in predicting mock juror ratings of responsibility, guilt, and sentencing recommendations were explored without a priori hypotheses. Results will add to the juror decision-making literature by being among the first to examine interactions among adolescent defendant age, gender, and psychosocial maturity in an experimental design, and implications regarding the inclusion of maturity information in juvenile proceedings are discussed.

Methods

Participants

Participants were recruited to the study from Amazon Mechanical Turk global crowdsourcing system (MTurk) and the student body of a college campus from the southwestern United States. Jury eligibility requirements vary between states; in order to be representative of jury-eligible populations throughout the U.S., the present study included only the juror eligibility criteria which are consistent across all states (U.S. Courts, n.d.); that is, participants must have been at least 18 years old and a U.S. citizen. A sample of 1,850 eligible participants were recruited in total; of these, 994 were recruited from MTurk and 856 were recruited via a college research participation program for students. A combination of both MTurk and student participants was used to counteract limitations in both samples (e.g., generalizability, attention).

An a priori power analysis revealed that with $α$ = .05, a minimum N = 812 would produce significant power to detect all main and interaction effects in the 3 × 2 × 4 multivariate analysis of covariance (MANCOVA). For equal distribution across 24 conditions (N = 35) total N = 840 was required. Participants were only included for final analysis if they correctly answered three attention checks, which asked participants to recall the psychosocial maturity, age, and gender of the defendant (unless they were in the control psychosocial maturity condition, in which case they were only asked 2 attention check questions). This a priori exclusion criteria resulted in a final analytic sample of N = 862 (n_MTurk = 343, n_college = 519).¹ The demographic information for both the full sample and the final analytic sample is reported in Table 1. Participants in the final analytic sample were between 18 and 73 years old (M = 27.81, SD = 11.47), primarily female (58.8%), and identified mostly as Hispanic (51.9%) or White (33.4%). The MTurk sample consisted of participants who were significantly more likely to be older, male, White, conservative, and having completed a higher level of education.

Table 1.

Demographic Information.

Variable	Full sample	Analytic sample
Variable	N = 1,850	N = 862
Age M (SD)	29.82 (12.12)	27.81 (11.47)
Sex N (%)
Male	859 (46.7)	351 (40.8)
Female	975 (53.0)	506 (58.8)
Prefer not to answer	6 (0.3)	3 (.3)
Race/ethnicity N (%)
African American or Black	291 (15.8)	87 (10.1)
Asian	38 (2.1)	17 (2.0)
White	739 (40.2)	287 (33.4)
Hispanic or Latino	727 (39.6)	446 (51.9)
Middle Eastern	4 (0.2)	3 (0.3)
American Indian or Alaskan Native	20 (1.1)	7 (0.8)
Native Hawaiian or other Pacific Islander	4 (0.2)	3 (0.3)
Other	15 (0.8)	10 (1.2)

Note. Compared to participants who passed all three attention checks (i.e., the analytic sample), participants who failed attention checks (i.e., excluded participants) were significantly older (M = 31.64, SD = 12.42, t = −6.76, p = .021). More male participants [ $Χ^{2}$ (1, N = 1,840) = 22.36, p < .001], White participants [ $Χ^{2}$ (1, N = 1,838) = 31.40, p < .001], and Black participants [ $Χ^{2}$ (1, N = 1,838) = 39.63, p < .001] were also excluded, whereas more Hispanic participants were included [ $Χ^{2}$ (1, N = 1,838) = 102.38, p < .001].

Procedures

An electronic informed consent form was provided to participants prior to the start of the study, outlining the procedures of the study, what they would be asked to do, the approximate length of participation, and affirming their eligibility to participate. MTurk participants were informed that they would receive $1.25 for their completion of the study, and college student participants were informed that they would receive course credit for their completion of the study.²

Participants were randomly assigned to one of 24 conditions in a 4 (Psychosocial Maturity) × 3 (Age) × 2 (Gender) between-participants experimental design. Participants first read a set of jury instructions that described factors the law requires they consider when making judgments about the defendant. They were then asked to read a criminal court vignette (shown below) and imagine they were a juror making judgments about the defendant. The bracketed text shows the instructions that varied depending on the experimental condition the participant was assigned to. The vignette read:

John [Sally] is a 13-year-old [15-year-old, 17-year-old] male [female] who lives with his [her] mother, father, and sister, gets average grades in school, and has never been in trouble with the police before. One day when no one was home, John [Sally] took his [her] mother’s car, even though he [she] did not have a driver’s license, to pick up a friend nearby who had been drinking alcohol and needed a ride home. The evidence suggests that while driving, John [Sally] answered a text message from his [her] friend, causing him [her] to swerve and hit a person biking on the side of the road. The person fell to the ground and did not get up, and John [Sally] drove away. The victim is in critical condition at the hospital due to injuries from the hit. Due to the seriousness of the crime, John [Sally] is being tried as an adult in criminal court with felony vehicular hit-and-run charges. A guilty verdict for an adult in criminal court will result in John [Sally] being a registered felon for the rest of his [her] life, with a permanent criminal record.

Psychosocial maturity was manipulated such that the defendant was depicted as having one of four maturity levels (adapted from Hughes & McPhetres, 2016), as determined by an expert witness: less mature than same-aged peers, equally mature as same-aged peers, more mature than same-aged peers, or a control condition in which no maturity information was presented. Participants who were not in the control condition were provided with specific information regarding the juvenile’s maturity as assessed by an expert witness:

Dr. Smith is the child psychologist who evaluated John [Sally] and gave testimony as an expert witness at the trial about John’s [Sally’s] developmental maturity. Dr. Smith has a Master’s degree in child development and a PhD in developmental psychology, 15 years of experience as a licensed child psychologist, and has testified in court as an expert witness in dozens of cases involving children and adolescents. Dr. Smith reported that John [Sally] was less [equally, more] mature compared to other youth of his [her] age. Specifically, Dr. Smith stated that compared to other youth his [her] age, John [Sally] had less [equal, greater] ability to control his [her] impulses and think before making decisions, consider the future consequences of his [her] behavior, and think about the risks associated with his [her] actions.

After reading the vignette, participants were asked to complete a survey in Qualtrics in which they made judgments regarding the defendant’s culpability, a determination of guilt, and sentencing recommendations. Following their judgments regarding the case vignette, participants answered a variety of questions regarding their endorsement of adolescent stereotypes, general attitudes toward juvenile culpability, juror bias, and demographics. All methods were approved by The University of Texas at El Paso Institutional Review Board.

Measures

Primary Variables

Perceived Responsibility

Mock juror perceptions of criminal responsibility were assessed with two questions (adapted from Hughes & McPhetres, 2016): “How responsible is John [Sally] for injuring the victim?” and “How much blame does John [Sally] deserve?” Both questions were rated on a Likert-type scale from 1 (not at all) to 7 (extremely/very much). A total perceived culpability score was obtained using the average score from these two questions, with higher scores indicating the participant perceived the defendant to be more responsible for the crime (α = .765).

Determination of Guilt

Perceived guilt of the defendant was assessed using a question adapted from Hughes and McPhetres (2016): “How likely is it that you would find John [Sally] guilty of vehicular hit-and-run?” Responses were rated on a Likert-type scale from 1 (not at all) to 7 (extremely likely), with higher scores indicating a greater likelihood the participant would find the defendant guilty. Participants were also asked “What verdict would you give to John [Sally]?,” with dichotomous response options of either Guilty (1) or Not Guilty (0).

Sentencing

Six questions measured how the participant believed the defendant should be treated during their sentencing proceedings. Four statements (adapted from Bradley et al., 2012) read: “John [Sally] is capable of being rehabilitated” (reverse-coded), “John [Sally] is likely to commit future violent crimes,” “John [Sally] should be punished for what he [she] did,” and “The judge should take John’s [Sally’s] age into account when sentencing him [her]” (reverse-coded). Two statements were created for the current study: “The judge should take John’s [Sally’s] maturity into account when sentencing him [her]” (reverse-coded), and “John [Sally] is dangerous.” All six statements were rated on a Likert-type scale from 1 (strongly disagree) to 5 (strongly agree), and an average score was obtained. Reliability for the composite score evidenced low reliability (α = .566). Therefore, an exploratory factor analysis (EFA) was conducted to determine underlying factors within the sentencing scale. The question regarding whether the defendant should be punished exhibited a low communality (0.282) and was omitted from scale calculation. Omitting this question increased reliability (α = .632); although this level is considered questionable by traditional rules of thumb and, therefore, results should be interpreted with caution. Higher average scores indicated that the defendant was deserving of more severe treatment during sentencing proceedings.

Finally, participants’ perspectives of the appropriate sentencing outcome for the defendant was assessed by asking participants to select how severely they believe the defendant should be sentenced (adapted from Campbell & Schmidt, 2000): “Please choose from the following list which sanction is the most severe outcome appropriate for John [Sally]: no punishment (1), paying a fine/restitution (money to the victim’s family; (2), delayed ability to obtain driver’s license (3), community service (4), education order (i.e., education for behavioral problems or vehicle safety; (5), probation/house arrest (6), detention in a juvenile facility for less than 1 year (7), detention in an adult facility for less than 1 year (8), detention in an adult facility for 1-5 years (9), detention in an adult facility for more than 5 years (10).” Higher scores indicated the participant perceived a more punitive sentence as the most appropriate outcome.

Covariates

Endorsement of Adolescent Stereotypes

The five myths of adolescent development identified by Offer and Schonert-Reichl (1992) were adapted into a scale for the purposes of this study. Participants were asked how much they agreed or disagreed with several myths of adolescent development, such as “Adolescence is a time of increased emotionality” and “Puberty is a negative event for adolescents.” Seven adolescent stereotypes specific to culpability were also created by the research team, such as “Adolescents are impulsive” and “Adolescents are poor decision-makers.” Responses were scored on a Likert scale from 1 (Strongly Agree) to 5 (Strongly Disagree), and all responses were reverse-coded. An average score of the twelve items was obtained, such that higher scores indicated greater endorsement of adolescent stereotypes. Reliability for the final scale was good (α = .783).

Juvenile Culpability

The Juvenile Culpability Scale (JCS; Crosby et al., 1995) gauged how much criminal responsibility participants attribute to juveniles generally. An adapted version of this scale, the Juvenile Culpability Scale-Adapted Form (JCS-A), was created by D. L. Warling (2001) to measure perceptions of juvenile culpability not specific to capital murder cases, and this adapted form was used in the current study. The JCS-A consisted of six statements such as “Juveniles do not have the maturity or life experience to appreciate fully all of the possible consequences of their actions.” Participants were asked to indicate how much they agree with each statement on a 7-point Likert scale ranging from 1 (Strongly Agree) to 7 (Strongly Disagree). Responses on the six items were averaged to obtain a composite score, with higher scores indicating that participants attribute less criminal responsibility to juvenile defendants due to their age and/or immaturity (α = .695).

Demographics

Participants answered demographic questions regarding their political values (from 1–Very Conservative to 5–Very Liberal), education (1–Less than high school to 6–Post-college degree), number of children (and biological sex of children), experience with adolescents (1–I never interact with adolescents to 8–I interact with adolescents every day), and knowledge about adolescent development (1–Not knowledgeable at all to 5–Extremely knowledgeable). Participants also reported self-perceived socioeconomic status using the MacArthur Scale of Subjective Social Status (Goodman et al., 2001), which asks participants to rate themselves relative to other people and their communities and in the U.S. on a ladder from 1 (people who have the least money, least education, and the least respected jobs or no job; the lowest standing in the community) to 10 (people who have the most money, the most education and the most respected jobs; the highest standing in their community). Finally, participants were asked to select yes (1) or no (0) for whether themselves, their child or anyone else in their family had ever been arrested or convicted and whether themselves or anyone in their household worked in law enforcement or in the legal system.

Analytic Plan

A 4 × 3 × 2 MANCOVA was conducted to examine the main effects of age, gender, and maturity on mock juror perceptions of responsibility, guilt, and sentencing recommendations, and all potential 2-way and 3-way interaction effects among variables. Assumptions of the MANCOVA design were tested prior to analyses. Dependent variables included responsibility, guilt (continuous), sentencing severity, and appropriate sanction. Given that dichotomous outcomes are not appropriate for a MANCOVA design, guilt–dichotomous was not included in the main design and was instead explored in later logistic regression analyses. Control variables included the following: Participant demographics (i.e., gender, age, race/ethnicity, self-perceived social status, and political values), juvenile culpability and endorsement of adolescent stereotypes measures, self-reported experience interacting with adolescents, and number of children. Multivariate effects were examined using Pillai’s trace (p < .05); this statistic is most robust to violations of normality and homogeneity of variance (Olson, 1974, 1979). Univariate effects were examined using F-statistics (p < .05). If multivariate and univariate effects were significant, simple effects were examined using pairwise comparisons of estimated marginal means (i.e., the estimated means if the groups did not differ on the covariates of interest). There were not enough participants in the equally mature 15-year-old conditions to calculate estimated marginal means, and as such these conditions were not considered in pairwise comparisons. Sidak adjustments were utilized to account for familywise error with multiple comparisons; this adjustment method was selected because it is less conservative than the Bonferroni adjustment and does not assume equal sample sizes (Lee & Lee, 2018).

Results

Descriptive statistics for all outcome variables are reported in Table 2. All multivariate main and interaction effects are reported in Table 3. Of the control variables, there were significant multivariate effects for gender [Pillai’s Trace = 0.01, F(4, 770) = 2.54, p < .05)], age [Pillai’s Trace = 0.02, F(4, 770) = 4.13, p < .01)], SES [Pillai’s Trace = 0.03, F(4, 770) = 6.10, p < .001)], juvenile culpability [Pillai’s Trace = 0.07, F(4, 770) = 15.40, p < .001)], adolescent stereotypes [Pillai’s Trace = 0.04, F(4, 770) = 7.05, p < .010)], and adolescent experiences [Pillai’s Trace = 0.01, F(4, 770) = 2.67, p < .05)]. There were no significant multivariate effects for race/ethnicity, political leaning, or number of children.

Table 2.

Descriptive Statistics of Dependent Variables.

Variable	M	SD	Range
Guilt (dichotomous)^a	0.85	0.35	0–1
Guilt (continuous)	5.42	1.36	1–7
Responsibility	5.74	1.13	1.5–7
Sentencing severity (Likert)	2.00	0.69	1–4.4
Appropriate sanction	5.85^b	2.41	1–10

0 = not guilty and 1 = guilty.

5 = “Education order (i.e., education for behavioral problems or vehicle safety)” and 6 = “Probation/house arrest.”

Table 3.

4 (Psychosocial Maturity) × 3 (Age) × 2 (Gender) MANCOVA Test of Multivariate Effects.

Variable	Pillai’s trace	F	df	Error df	$η_{p}^{2}$
Covariates
Gender^a	0.01 *	2.54	4	770	0.01
Age	0.02 **	4.13	4	770	0.02
Race/ethnicity^b	0.01	1.28	4	770	0.01
SES	0.03 ***	6.10	4	770	0.03
Political leaning	0.01	1.90	4	770	0.01
Juvenile culpability	0.07 ***	15.40	4	770	0.07
Adolescent stereotypes	0.04 ***	7.05	4	770	0.04
Adolescent experience	0.01 *	2.67	4	770	0.01
No. children	0.01	1.78	4	770	0.01
Main effects
PSM condition	0.05 ***	3.49	12	2,316	0.02
Age condition	0.01	0.69	8	1,542	0.00
Gender condition	0.02 **	4.43	4	770	0.02
Interaction effects
PSM × age	0.03	1.04	20	3,092	0.01
PSM × gender	0.01	0.87	12	2,316	0.00
Age × gender	0.02	1.59	8	1,542	0.01
PSM × age × gender	0.03	1.34	20	3,092	0.01

Note. PSM = psychosocial maturity.

0 = female, 1 = male.

0 = nonwhite, 1 = White.

p < .05. **p < .01. ***p < .001. Bold print indicates significant effects.

There were significant multivariate main effects for psychosocial maturity [Pillai’s Trace = 0.05, F(12, 2316) = 3.49, p < .001)] and gender [Pillai’s Trace = 0.02, F(4, 770) = 4.43, p = .002)]. There were no significant multivariate interaction effects. Univariate effects for each of the outcome variables are reported in Table 4.

Table 4.

4 (Psychosocial Maturity) × 3 (Age) × 2 (Gender) MANCOVA Test of Univariate Effects.

Variable	df	Responsibility (Likert)^a		Guilt (Likert)^b		Sentence (Likert)^c		Sentence (Sanction)^d
Variable	df	F	$η_{p}^{2}$	F	$η_{p}^{2}$	F	$η_{p}^{2}$	F	$η_{p}^{2}$
Covariates
Gender^e	1	0.09	0.00	0.01	0.00	8.02 **	0.01	2.44	0.00
Age	1	3.26	0.00	0.09	0.00	6.14 *	0.01	3.26	0.00
Race/ethnicity^f	1	2.97	0.00	2.00	0.00	1.61	0.00	0.52	0.00
SES	1	0.76	0.00	0.02	0.00	22.88 ***	0.03	0.79	0.03
Political leaning	1	1.04	0.00	0.82	0.00	3.82	0.01	0.34	0.00
Juvenile culpability	1	10.82 **	0.01	23.05 ***	0.03	36.84 ***	0.05	11.45 ***	0.02
Adolescent stereotypes	1	23.73 ***	0.03	8.84 **	0.01	4.73 *	0.01	1.79	0.00
Adolescent experience	1	1.28	0.00	2.34	0.00	0.12	0.00	9.48 **	0.01
No. children	1	4.48 *	0.01	0.42	0.00	2.64	0.00	0.04	0.00
Main effects
PSM condition	3	7.63 ***	0.03	9.04 ***	0.03	0.87	0.00	1.61	0.01
Age condition	2	0.30	0.00	0.70	0.00	1.15	0.00	0.19	0.00
Gender condition	1	1.11	0.00	0.94	0.00	1.62	0.00	11.33 ***	0.01
Interaction effects
PSM × age	5	0.59	0.00	1.92	0.01	1.17	0.01	0.94	0.01
PSM × gender	3	0.12	0.00	0.84	0.00	0.59	0.00	1.52	0.01
Age × gender	2	1.31	0.00	2.66	0.01	1.95	0.01	1.36	0.00
PSM × age × gender	5	0.57	0.00	1.43	0.01	1.59	0.01	.42	0.00

Note. PSM = Psychosocial maturity. Error df = 773.

R² = .099, Adjusted R² = .064.

R² = .098, Adjusted R² = .063.

R² = .211, Adjusted R² = .180.

R² = .082, Adjusted R² = .046.

0 = female, 1 = male.

0 = nonwhite, 1 = white.

p < .05. **p < .01. ***p < .001. Bold print indicates significant effects.

Responsibility

There was a significant main effect of psychosocial maturity on mock jurors’ ratings of responsibility F(3, 770) = 7.63, p < .001 (see Figure 1). Pairwise comparisons revealed that when the adolescent defendant was depicted as less mature than same-aged peers, they were seen as less responsible for the crime (M = 5.46) than when the adolescent was depicted as equally mature (M = 5.95, p = .046), more mature (M = 5.75, p = .044), or where no maturity information was provided (M = 5.91, p < .001). In other words, mock jurors perceived less mature juvenile defendants as less responsible for the hit-and-run than juveniles who were equally mature or more mature. When mock jurors were provided with information about the juveniles’ diminished maturity, they viewed the juvenile as less responsible than when no information about maturity was provided. There were no main effects of age or gender or interaction effects on mock jurors’ ratings of the juvenile’s responsibility. Additionally, only the covariates of juvenile culpability F(3, 770) = 10.82, p < .01, adolescent stereotypes F(3, 770) = 23.73, p < .001, and number of children F(3, 770) = 4.48, p < .05 had a significant main effect on responsibility ratings.

Figure 1.

Main effect of psychosocial maturity on responsibility (Likert).

Guilt

Like perceptions of responsibility, there was also a main effect of psychosocial maturity on mock jurors’ reported likelihood of finding the defendant guilty F(3, 770) = 9.04, p < .001 (see Figure 2). Mock jurors reported that they would be less likely to find the less mature juvenile guilty (M = 5.18) than the adolescent who was equally mature (M = 5.91, p = .006), or where no maturity information was given (M = 5.66, p < .001). Mock jurors also reported that they would be less likely to find the more mature adolescent guilty (M = 5.22) than the adolescent who was equally mature (p = .012), or where no maturity information was given (p = .002). There were no main effects of age or gender or interaction effects on mock jurors’ reported likelihood of finding the defendant guilty. Additionally, only the covariates of juvenile culpability F(3, 770) = 23.05, p < .001 and adolescent stereotypes F(3, 770) = 8.84, p < .01 had a significant main effect on perceptions of guilt.

Figure 2.

Main effect of psychosocial maturity on guilt.

The dichotomous measure of guilt was also explored using a logistic regression analysis with the same main effects, interaction effects, and covariates included in the model. The logistic regression was statistically significant, $Χ^{2}$ (19, N = 811) = 59.28, p < .001. Results were somewhat consistent with the MANCOVA results, with psychosocial maturity being the only significant main or interaction effect. The odds that a participant found the defendant guilty were 6.61 times higher when they were not provided with any maturity information as compared to when the defendant was described as less mature than their peers. The odds that a participant found the defendant guilty were also 7.58 times higher when the defendant was depicted as equally mature as compared to when they were depicted as more mature. The results of the full logistic regression model are displayed in Table 5.

Table 5.

Logistic Regression of Dichotomous Guilty Verdict Outcome.

Variable	B	SE B	Wald X²	Odds ratio
Covariates	.279	.234	1.415	1.321
Gender^a	.002	.014	.014	1.002
Age	−.144	.265	.296	.866
Race/ethnicity^b	−.114	.065	3.088	.893
SES	−.103	.094	1.177	.903
Political leaning	.861	.214	16.133	2.365
Juvenile culpability	.080 ***	.232	.119	1.084
Adolescent stereotypes	−.096	.049	3.853	.909
Adolescent experience	.091 *	.161	.315	1.095
No. children	.279	.234	1.415	1.321
Main effects
No information (vs. low PSM)	1.888 **	.766	6.080	6.606
Equal PSM (vs. low PMS)	−.164	.860	.036	.849
High PSM (vs. low PSM)	−2.190	1.424	2.365	.112
13-years-old (vs. 17-years-old)	1.355	1.796	.569	3.876
15-years-old (vs. 17-years-old)	.945	.924	1.045	2.573
Female (vs. male)	1.446	1.170	1.527	4.245
Interaction effects
PSM × age	.341	.340	1.001	1.406
PSM × gender	.512	.445	1.325	1.668
Age × gender	.307	.555	.305	1.359
PSM × age × gender	−.078	.217	.130	.925

Note. PSM = psychosocial maturity.

0 = female, 1 = male.

0 = nonwhite, 1 = White.

p < .05. **p < .01. ***p < .001. Bold print indicates significant effects.

Sentencing

There was a main effect of gender on the severity of the sentence mock jurors assigned to the juvenile defendant F(1, 770) = 11.33, p < .001 (see Figure 3). Specifically, mock jurors assigned a more severe sentence to the female defendant (M = 6.19) than the male defendant (M = 5.54, p < .001). For reference: A score of 5 on this measure referred to “Education order (i.e., education for behavioral problems or vehicle safety),” a 6 indicated “Probation/house arrest,” and a 7 indicated “Detention in a juvenile facility for less than 1 year.” There were no main effects of age or psychosocial maturity or interaction effects on mock jurors’ selection of appropriate sanction. Only the covariate of juvenile culpability had a significant main effect on the severity of sentence selected F(3, 770) = 11.45, p < .001.

Figure 3.

Main effect of gender on sentencing outcome.

Additionally, there were no main or interaction effects on mock jurors’ Likert ratings of how severely they believed the defendant should be treated during sentencing. The covariates of gender F(3, 770) = 8.02, p < .01, age F(3, 770) = 6.14, p < .05, SES F(3, 770) = 22.88, p < .001, juvenile culpability F(3, 770) = 36.84, p < .001, and adolescent stereotypes F(3, 770) = 4.73, p < .05 had a significant main effect on Likert ratings of sentencing severity.

Discussion

Juveniles’ still-developing psychosocial maturity can hinder their decision-making in certain contexts, making them less responsible than adults for their criminal behavior. This fact is not only supported by developmental research but has also been recognized by U.S. Supreme Court precedent. Understanding how knowledge about juveniles’ maturity can influence jurors’ perceptions and subsequent treatment of juvenile offenders is therefore essential in maintaining fair and developmentally appropriate legal proceedings. The current study examined how information about adolescent defendants’ psychosocial maturity, age, and gender influenced mock jurors’ perceptions of culpability, guilt, and sentencing recommendations.

Mock jurors’ perceptions of responsibility and guilt were primarily in line with developmental research that suggests adolescents are indeed less culpable for criminal behavior primarily as a result of their developmental immaturity rather than their physical age (Cauffman & Steinberg, 2000). Informing jurors that the juvenile defendant was less psychosocially mature than their peers mitigated their perceptions of criminal responsibility, such that juveniles who were depicted as less mature were seen as less responsible than juveniles who were depicted as equally mature or more mature. Mock jurors also reported that they would be less likely to find a juvenile defendant guilty when they were depicted as less mature as compared to when they were depicted as equally mature. These findings were consistent with hypotheses and indicate that mock jurors understand that diminished psychosocial maturity is associated with less criminal culpability beyond the effects of age. Although the null effects of age were not hypothesized, they do indicate that the mock jurors were able to distinguish between age and maturity and appropriately placed a greater emphasis on maturity in their decision-making process.

Contrary to hypotheses, however, mock jurors also thought that more maturity was associated with less criminal culpability. Mock jurors reported being less likely to find the more mature juvenile guilty than the equally mature juvenile. One possible explanation for this finding is that mock jurors might have viewed more mature juveniles as less likely to recidivate and more deserving of a second chance. Research does indeed support that more psychosocially mature youth are less likely to recidivate (McCuish et al., 2020; Monahan et al., 2009; Rocque et al., 2019). Jurors might therefore accurately perceive a more mature adolescent as more likely to learn from their mistakes and avoid similar situations in the future, especially when the offense was committed in a high-stress situation such as the current study vignette. An adolescent with average maturity, however, might be viewed as mature enough to have “known better,” but not mature enough to avoid similar criminal behavior in the future.

One of the most interesting findings from this study was the effect that no maturity information played in jurors’ perceptions of juvenile defendants. Mock jurors viewed a juvenile defendant as more responsible for the crime and reported being more likely to assign guilt when no maturity information was provided as compared to when the juvenile was depicted as less mature than their same-aged peers, as hypothesized. However, mock jurors were also more likely to assign guilt when no maturity information was provided than when the juvenile was depicted as more mature. In other words, maturity information mitigated jurors’ perceptions of juvenile defendants nearly across the board—regardless of whether the juvenile was depicted as more or less mature than their peers. These findings are in line with prior research suggesting that jurors need to be given explicit information regarding an adolescent defendant’s maturity in order to recognize the association between maturity and culpability (Hughes & McPhetres, 2016). Not addressing developmental maturity might therefore put juvenile defendants at a disadvantage when they face a jury trial.

Finally, findings from the current study indicated that girls were treated more harshly than boys in sentencing. For boys, an appropriate sentence was perceived to be between an education order (i.e., education for behavioral problems or vehicle safety) and probation/house arrest; for girls, an appropriate sentence was perceived to be between probation/house arrest and detention in a juvenile facility for less than 1 year. Although this finding was contrary to the initial hypothesis, there is some research to suggest that girls can be treated more harshly than boys particularly during later proceedings such as disposition (Carr et al., 2008; MacDonald & Chesney-Lind, 2001). That the current study only saw gender differences in mock jurors’ sentencing decisions would support the idea that girls are treated more harshly than boys as they progress further through the juvenile justice system. This disparity could be due to a greater social acceptance of boys’ misbehavior and delinquency in comparison to girls’ (i.e., “boys will be boys”) or the idea that girls require more supervision than boys.

Implications and Future Directions

These findings offer several important implications for juveniles in the justice system, and many opportunities for future research. Overall, these findings indicate that jurors are indeed able to recognize psychosocial maturity as a construct distinct from physical age and its relation to juvenile culpability when they are provided with relevant maturity information. Although this understanding is not perfect (i.e., they perceived both less mature and more mature juveniles as less culpable), omitting maturity information altogether resulted in more severe treatment of juvenile defendants. Despite the importance of psychosocial maturity in juveniles’ criminal culpability, it is a factor rarely considered in the courtroom in a formal capacity. Yet, for a juvenile defendant in criminal court who exhibits low psychosocial maturity, providing such information to the jury could mean the difference between a verdict of guilty or not guilty. Defense attorneys or judges should consider incorporating information regarding juvenile maturity beyond their physical age alone into the courtroom to help jurors reach developmentally informed legal outcomes for juvenile defendants more consistent with their reduced culpability.

The maturity information provided to mock jurors in this study evaluated juvenile defendants in relation to same-aged peers (i.e., more mature, equally mature, or less mature than same-aged peers). Although any maturity information generally led jurors to more developmentally appropriate conclusions, juveniles were seen as the least responsible and guilty when they were depicted as less mature than other peers their same age. It is important to note that not all juveniles can be accurately described as less mature than their peers; however, adolescents who are involved with the justice system tend to be less psychosocially mature than their non-justice involved peers (Dmitrieva et al., 2012; Monahan et al., 2009; Simmons et al., 2020). Discussion of juvenile maturity might therefore help jurors to reach more developmentally appropriate decisions for juvenile defendants.

Regardless of where a specific adolescents’ maturity stands in relation to their peers, adolescents as a group are less mature than adults and therefore less culpable than adults for criminal behavior (Cauffman & Steinberg, 2000; Icenogle et al., 2019; Steinberg & Cauffman, 1996). This has been recognized by the U.S. Supreme Court, which is why adolescents as a group—regardless of individual maturity—are not able to be sentenced to death (Roper v. Simmons, 2005) or mandatory life without parole (Miller v. Alabama, 2012). Although the current study did not examine the effects of individual maturity assessments versus more general information about the diminished psychosocial maturity of adolescents as a group, the findings indicated that any maturity information led jurors to more lenient and developmentally appropriate outcomes for juvenile defendants. In the absence of an individual assessment of juvenile maturity general maturity information may provide a suitable replacement, though this assertion would need to be studied further.

This research also provides implications for how juvenile psychosocial maturity might influence the decision-making of legal actors beyond jurors, and the subsequent legal outcomes decided by those actors. Although jurors are responsible for making an extremely consequential legal decision—a verdict of guilty or not guilty—they do not typically determine sentencing; this decision is usually left to a judge. Jurors are likely unfamiliar with what would constitute an average or appropriate sentence, whereas judges are equipped with prior experience and/or sentencing guidelines to help them reach a fair determination. Indeed, research suggests that laypeople are generally unfamiliar with common sentencing terminology and practices (Feilzer, 2015; Marsh et al., 2019). Future research should examine how judicial perceptions and decision-making are also impacted by information about an adolescent defendant’s psychosocial maturity, as this information may have different effects on different legal actors.

Strengths and Limitations

The current study had several strengths, which were achieved by addressing some of the limitations present in prior literature on psychosocial maturity and juror decision-making. First, the current study provided greater ecological validity than previous studies by using a crime serious enough (i.e., vehicular hit-and-run) and age conditions old enough to warrant adolescent transfer to adult court. This kind of ecological validity is an important consideration in mock juror research concerning juvenile defendants, given that jurors would typically only make judgments pertaining to juveniles’ legal outcomes if the juvenile was transferred to criminal court. Second, this study utilized an experimental design which allowed for manipulation of a juvenile defendant’s level of psychosocial maturity—a manipulation that would be impossible to achieve in assessing actual juvenile outcomes. Third, the current study included a control condition in which no information about psychosocial maturity was provided to the participants; few existing studies that examined the effect of psychosocial maturity information on juror decision-making have included control conditions. This control condition allowed for a crucial comparison between any maturity information being provided to jurors and a lack of information altogether, which yielded some of the most important results.

However, the current study was not without limitations. A limitation of this study was that the exclusion criteria drastically reduced the analytic sample and resulted in the equally mature 15-year-old conditions being omitted from pairwise comparisons. The high rate of attention check failure in the “equally mature” condition in particular³ could be due to participants equating “equal” to “average.” When maturity was described as “less than” or “greater than” same-aged peers, participants may have been more likely to encode and retain this information than when maturity was explicitly described as “average.” Given that participants in all conditions failed attention checks at a high rate, attention check failure was likely due to participants simply not remembering the information. This exclusion criterion was originally set to ensure that participants indeed remembered the information about the defendant’s psychosocial maturity, age, and gender that was provided to them. However, it is important to note that jurors are not provided with attention checks during actual trials. As such, the argument could be made that utilizing the full sample—regardless of attention check failure—would be more ecologically valid in juror decision-making research. Indeed, the current study found nearly identical multivariate effects regardless of whether the full sample or the analytic sample was used. Although participants in the full sample struggled to recall information about the defendant’s psychosocial maturity, age, and gender in the attention checks, this information appeared to influence their perceptions of the juvenile defendant in a manner consistent with that of participants who were able to recall information about the defendant. Finally, as we did not evaluate participants’ conceptualization of psychosocial maturity following the receipt of expert testimony, it is possible that some participants may not have fully understood the concept of psychosocial maturity or viewed it as resulting from a cognitive deficit of some sort, which may have affected their guilt and sentencing determinations. However, this is like the real-world conditions of a courtroom in which jury members may not fully comprehend expert testimony, despite making determinations based on such testimony.

Conclusion

Although prior research on the effects of psychosocial maturity on juror perceptions and decision-making is limited, the present findings suggest it is an important topic ripe with opportunities for future research. The current study indicated that not providing jurors with information about a juvenile defendant’s psychosocial maturity could put defendants at a disadvantage during legal proceedings; being explicit about psychosocial maturity and its influence on culpability, however, has the potential to lead jurors to more developmentally appropriate verdicts for adolescent defendants.

Footnotes

Acknowledgements

We would like to acknowledge Krystia Reed, Caitlyn Muniz, James Wood, and Anna Drozdova for their thoughtful feedback and continuous support. The authors have no conflicts of interest to disclose.

Data Availability

Materials and analysis code for this study are not available. This study was not preregistered.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was supported by The University of Texas at El Paso Dodson Fund.

ORCID iD

April Gile Thomas

Notes

Author Biographies

Isabelle M. Clough is a research analyst at the Minnesota Judicial Branch. She earned her PhD in Legal Psychology at The University of Texas at El Paso, where her research focused on adolescents’ psychosocial maturity and delinquency.

April Gile Thomas is an Associate Professor of Legal Psychology at The University of Texas at El Paso. Her research applies a developmental perspective to understanding juvenile delinquency. Through her research, she aims to improve juvenile justice system policies to make them more developmentally appropriate for youthful offenders.

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The More You Know: Information About Juvenile Psychosocial Maturity Influences Mock Jurors’ Perceptions and Decision-making

Abstract

Keywords

Juvenile Psychosocial Maturity and Legal Culpability

Juror Legal Decision-making

Age

Developmental Maturity

Gender

The Present Study

Methods

Participants

Procedures

Measures

Primary Variables

Perceived Responsibility

Determination of Guilt

Sentencing

Covariates

Endorsement of Adolescent Stereotypes

Juvenile Culpability

Demographics

Analytic Plan

Results

Responsibility

Guilt

Sentencing

Discussion

Implications and Future Directions

Strengths and Limitations

Conclusion

Footnotes

Acknowledgements

Data Availability

Declaration of Conflicting Interests

Funding

ORCID iD

Notes

Author Biographies

References