From the Trimet drivers side

When Billy Badass gets on board and starts causing a ruckus, it automatically registers on my radar as I guide The Beast down the road. First, my attention is distracted from the normal sounds one hears on a bus. That's dangerous, because our focus needs to be mostly centered upon a wide view of the road. Once I'm distracted, the chances of making a costly mistake that could injure many people off or on my bus is multiplied

https://fromthedriverside.blogspot.com/2019/04/protect-me-not-my-assailant.html