You have to wonder about the kind of person who thinks they can make a difference doing this, and then wants to do it.

Certainly they are after attention, first. That's dangerous. They are likely to intervene in situations which are of no consequence.

Secondly, they identify with a fantasy character. That's OK to an extent, not to the extent of dressing like them and "patrolling" the streets.

Third, they could get into one hell of a lot of trouble fast. Who would take them seriously? And anyone that narsissistic would make it about them.

Curtis Sliwa's Guardian Angels was an example of his grandiosity at work, and he staged fake rescues. For all I know they are still wandering around someplace, probably don't do any harm. At least they didn't dress up in Halloween costumes.

ER's COPS program looks to be a very good deal. The more eyes on the street the better. If I were them I'd have a very bright blue light, preferably rotating, which could be plugged into the cigarette lighter. I've seen a lot of loud parties and people silenced simply by cops flashing the lights. A badguy will clear out of an area if he sees a blue light moving around.