In recent years, the Mount Vernon Trail has been a low crime area. In the last year there was a report of a sexual assault (a groping from which the victim escaped) north of Old Town Alexandria. There is the occasional disturbed person who yells at trail users. Local law enforcement and the National Park Service which owns the trail have generally been responsive to reports of crimes, regardless of their nature.
Mostly the trail attracts helpful people like the Trash Walker. He’s a senior citizen who walks in the morning and picks up litter as he goes.
Last night, someone smashed a couple of park benches to bits. This incident occurred between National Airport and Slaters Lane, north of Old Town. Whoever did it exerted some serious energy, probably jumping up and down on the seats. It’s not the end of the world but I hope there isn’t more of this sort of thing.
A Few Spokes Shy of a Wheel 
That is sad! People should jump on trampolines, not park benches 😦