All Aboard: Light Rail,Mobility Justice,and the Future of Public Transit in Austin,TX: Authors’ Response to Commentaries

We thank both reviewers for their thoughtful feedback throughout the publication process. Their encouragement to think through the question of causality and consider alternative explanations has undoubtedly strengthened the piece. It has also helped us to reflect more on the work's limitations and better highlight what we can meaningfully extract from this single case study.

We contend that the Austin case demonstrates what is possible when a progressive local coalition informed by the principles of mobility justice unites around a local transportation initiative under broadly favorable political-economic conditions. We did not set out to establish a definitive formula for success across contexts. Local conditions across the country are too varied, the politics too volatile, and the regimes malleable. For example, in 2018, residents in Nashville, TN, voted down a proposed transit expansion 64–36 only to support a somewhat more modest measure in 2024 by almost the opposite margin.

Jen Nelles (2025) expresses some discomfort with our use of regime theory. We acknowledge that adapting regime theory to an electoral context diverges from its more typical application to post-electoral governance. Part of the power of regime theory—and why we chose to employ it here—is that it provides an inventory of the critical factions, interests, and perspectives at play in all manner of city and regional decision-making and planning efforts. The notion that interest groups align around specific proposals that advance their interests and assemble resources commensurate with achieving their goals seems to reflect reality and provide explanations for events that have the ring of truth. These explanations comport with the primary sources we assemble here.

On the related questions of explanation and causality raised by both reviewers, we agree with the points raised by Martin Horak (2025) that offer insight into precisely why Project Connect was approved by voters in 2020 after multiple other measures had failed in the past. Beyond a certain point, growing economic activity causes cities and regions to feel an undeniable strain on their infrastructure; the resultant time costs and other inconveniences represented by congestion simply become too much for residents to bear. This strain leads to a search for alternatives. There is no shortage of straight-ahead transit expansions funded by self-imposed tax increases across the country. Explanations for those cases often center on the project mix, geographic spread, and other factors that lead to public support or opposition. What is unique about the Austin case is not that the transit measure passed, but that it included multiple provisions solidly aligned with mobility justice goals. Horak notes that Austin's political economy is particularly “hospitable” for transit justice advocacy. We agree that this is part of the explanation, but simply because the environment is hospitable does not mean that progressive policy will result—see the prior failed ballot initiatives that litter Austin's history.

What then can we learn about what enables or constrains advocates in these contexts, as Horak (2025) asks? We agree with them that our case shows how activists can “from time to time” win significant victories. The existence of a unified progressive transit coalition is necessary but not sufficient to ensure this type of outcome. One thing is certain—without such a coalition, just outcomes would be unlikely to obtain. The regime history that we assemble in the paper demonstrates that over time, progressive organizations have formed and aligned in various ways with other actors to accomplish key goals. Key members at each decision point vary, but clearly, Austin has the capacity to support a broad array of progressive organizations acting at multiple scales across many different issue areas. These include transportation-specific organizations as well as others with a broader justice orientation.

For those looking for causality in our case, know that organizing matters. Yes, conditions will vary from place to place, and advocacy will not always lead to material wins. But if activists are not ready to strike while the iron is hot, to partner with public agencies when major ballot initiatives are being contemplated, and to put forward justice-oriented goals, their perspectives will not be represented. Organizing may not be definitive, but without it no progress is possible.