According to The Register, there were 1,400 incidents of crossing guard abuse (driving past while they're in the road, revving engines, shouting epithets, etc.) reported in the UK last year. Dozens of guards (they're called "lollipop ladies" because of the signs they carry and because, apparently, few of them are men) have been hit by cars.
Local councils are responding with 1) training and 2) the Routesafe Monitor, a double-headed video camera installed in the lollipop person's stop sign. The camera is activated when the sign is held up and monitors the situation before and behind. Anyone misbehaving while the sign is upright will be taped and (presumably) tracked down and remonstrated with.
The UK has a lot of law enforcement cameras. By one estimate, Londoners get snapped or taped more than 300 times per day. Who watches all of those feeds? Good question, but it doesn't work that way. The cameras are used (for the most part) reactively--after a crime is reported, the police go back and retrieve the relevant footage.
300 times. So what difference will a few more cameras make? Plenty: For the first time, law enforcement videocams are being put into the hands of semi-private individuals--in other words, citizens are being officially recruited in the video war on the criminal class. (And the cameras needn't be restricted to crossings--I like the image of a lollipop person, accosted on her walk home, waving her stop sign at an unsuspecting mugger as if she were holding off a vampire with a crucifix.)
This approach would be different from privately-owned videocams, whose footage belongs to the citizen and can only be secured via request (or subpoena)--under this regime, you're feeding your life (or parts of it) directly to a police database. It might be like a Twitter feed, in a twisted sort of way--some streams would be more interesting than others. Not that police HQ personnel would ogle your stream, of course.
I'm imagining a whole posse of officially-sanctioned vigilantes, each equipped with video cams and wireless links back to the station--a neighborhood watch on steroids driven by righteous anger and a bounty for each tape-enabled conviction. Of course, mostly they'd catch parking violations, pan-handling and jaywalking, but the law is the law.