Photo by Matt.Dunn.

In recent weeks, the Guardian Angels — the unarmed, volunteer crime patrollers — have stepped up their patrols on Metro trains. Aside from the rare beating, the Angels are generally a positive force, especially on a sprawling system like Metro, which has plenty nooks and crannies that are really difficult for police to monitor. Angel patrols have been stepped up after several fights on Metro this summer: in the wake of the 70-person brawl that broke out earlier this month, the Angels dedicated themselves to upping patrols around the Gallery Place/Chinatown station. They’ve started riding on Metrobuses more, as well. This is nothing new, of course — the Angels have a sizable presence in D.C. and are often quick to offer up their patented brand of group policing.

The increased presence paid off last Friday, when Angels detained three men after a fight broke out on a Green Line train. But one DCist commenter on that post was curious: is it actually legal for the Guardian Angels to detain someone like that?

According to MPD Lieutenant Damion Taylor of the Seventh District, the Angels are usually in the clear — it’s all about the intent of their actions.

“Generally, we do not encourage untrained and/or non-law enforcement personnel to approach or attempt to restrain violent or potentially otherwise dangerous individuals for obvious reasons,” Lt. Taylor wrote in an email. “However, in the event of some crimes in progress such as an Assault on another person, citizens acting within good faith (e.g. good samaritan observing a domestic assault) and otherwise reasonable means (e.g. immediately contacting police) generally will not be criminally charged by police officers,” he added.