Impact of poor evidence management on DNA profiling in sexual assault and homicide: A case report

Abstract

Increasing numbers of female victims of violent sexual assaults are being murdered with the aim of concealing the identity of the perpetrator. Proper handling and analysis of evidence is very important in gaining a conviction in many criminal cases. After evidence is collected, due precautions must be taken to ensure that the integrity of the sample is maintained, and chances of contamination are minimised. This paper presents a case study where improper handling of biological evidence led to loss of evidentiary value, and the semen could not be located on the vaginal swabs and victim’s garments due to improper preservation of samples. However, the DNA from the nail of a decomposed finger helped identify the victim, and the suspect was apprehended based on the clues given by her family.

Keywords

Evidence management biological evidence DNA profiling sexual assault identification

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