Negative perceptions about the safety of a commuter rail system can act as a barrier to using public transportation. When operational issues increase rider tension (i.e., crowding or worsening on-time performance), or the management capabilities of conductors and law enforcement personnel are called into question, an upsurge in passenger-on-passenger aggression may occur. In turn, riders concerned about their safety may retreat to personal vehicles or other forms of “less risky” transit, such as express buses. Modifying an interstitial estimation process, this study presents a new method of identifying where rider concerns about public safety concentrate. Using the commuter rail system of Los Angeles as a case study, specific inbound and outbound trip segments were found to exhibit different problems. Raw scores identify segments in need of greater train car supervision, and these segments differ from where discontented riders congregate (requiring customer service outreach). Tailored responses, focused on a few segments, stand to improve perceptions of safety and, ultimately, may increase ridership.