For those wondering like me what "bart" might be in this context, it seems to be the heavy rail "Bay Area Rapid Transit" system in San Francisco, California.
When I was riding BART around 2014.. 3 people died that year on the trains.
1 person stabbed to death from random altercation. 1 person punched and fell and cracked their head open. 1 person was in altercation, pushed and cut their knee on the floor. Died of infection from incident.