Trolley driver acquitted in case involving him crashing into another trolley, injuring 24

… not with the driver, and not even with the T—although both have a good deal of it—but with the DPU which has required asinine, "safety theater" speed restrictions for the Green Line which at best do nothing at at worst create confusing operating conditions which lead to incidents like this.

As best as I can tell—and I can't find these regulations anywhere but have heard from operators—the DPU at some point required that Green Line trains operate at no more than 10 mph when operating on any roadway (like in Mission Hill), crossing any roadway (like elsewhere on the B, C and E lines) or operating adjacent to a platform. From an operating standpoint, this creates longer trips which require more staff and trains to operate and slower trips for passengers.

But from an operating safety point of view, they make zero sense. First, on-street operation. There are several examples of on-street operation in the US (Philly, San Francisco, Toronto, and portions of some newer light rail and streetcar systems) and hundreds abroad and none have this sort of regulation. Streetcars in SF and Toronto and wherever else operate at or below the speed limit, just like, you know, cars and buses. So why does the T have these stupid rules? Who knows! The DPU decided it was "safer" and put it into place. And we all know how well the DPU has been doing with safety.

Crossing roadways is worse. Most of the roads the Green Line crosses have signals. When a car or bus gets to a green light, it goes the speed limit. But when a Green Line train gets to a light, it has to slow to 10 mph, cross the street, and then speed up. In many cases this means a constant yoyoing of speeds, rather than maintaining a constant speed. (Maybe there is some sense to a 10 mph limit when crossing non-signaled crossings, like exist on some portions of the B Line, but really, those should either be closed or signalized to permit more efficient operations.) If you want to see this in action, go down to the BU Bridge and watch as trains slow down to 10 mph to cross through a green light and then speed back up and see if it makes any sense as cars and buses and trucks all operate at 30 mph in parallel lanes.

Platforms are another ¯\_(ツ)_/¯. The Orange, Red and Blue lines and Commuter Rail don't have these issues, nor do light rail systems anywhere else in the world. It's not just pedestrian crossings: when a train is adjacent to a platform, it has to operate slowly, even if there is no pedestrian crossing. So even if a platform is basically just a walkway with a yellow line, with no pedestrian crossing, a train has to crawl along because someone might decide to jump in front. You know, just like the … no other lines.

What this adds up to are a bunch of rules which are there for the sake of being rules, but which have negligible-at-best individual safety improvements. But it becomes a "boy who cried wolf" situation: operators are now paying more attention to these rules that don't actually make things safer that they may lose situational awareness for the actual safety issues (like "train in front of me" or "Maserati taking an illegal left into the path of my train."

The Maserati thing is obviously the fault of the car driver, but it's possible that the 10 mph crossing rule is partially to blame. A lot of Green Line operators seem to honor the spirit of the rule, hitting the crossing at 10 mph, and then accelerate part way through. (In this case, the train was stopped at the light, so it may have pulled out at 10 mph and then applied more acceleration part way through.) If that's the case, a car driver may think the train is going to maintain the slow speed and attempt to cut in front of it, and then if the train accelerates, the car goes smush.

It also means that when there is a legitimate 10 mph limit (like through a construction zone) it seems like every other 10 mph limit (which are there because ¯\_(ツ)_/¯) so operators are less likely to be paying attention. Whereas if the speed limit was 30 across the line, the 10 mph zones would stand out more. In other words, if there's a boy crying wolf every 200 feet, when a real wolf shows up no one is going to notice. (The operator may still have fallen asleep, or something, and the T really should figure out the GLTPS thing that's way delayed, although apparently that was delayed partly because the T execs was trying to make it allow self-driving trains, rather than just making the existing trains safer. IOW instead of trying and failing to create self driving trains, we could have had a simpler "if there's a train in front of you, brake" system.)

TL;DR: DPU makes a bunch of dumb rules, operators have to pay attention to a bunch of dumb rules that don't make operation any safer, and that takes their focus off of the things that matter more.