The enforcement tactic in NYC w/r/t cyclist infractions is to have at least two cops sitting around ticketing every biker who goes by committing a minor infraction. The opportunity cost is everything else those officers could've been doing for those several hours (perhaps ticketing the numerous cars blowing through red lights at the very same intersection.)

I live in NYC, I have seen this happen.

Of course, it is much more difficult and disruptive to ticket a car that has just blown a red light at high speed, than a biker who has blown a red light. Unfortunately, the city isn't allowed to install red light cams in most places because of Albany. Red light cams would be a safe, fair counterpart to increased red light enforcement for bikes. That being said, very very very few people are injured and none are killed because of bikes running reds (neither collision in Central Park this year was at an intersection). Likely hundreds are injured and at least dozens are killed from cars running red lights every year.

NYPD says they don't even have the resources to investigate fatal car crashes. They didn't bother investigating the death of a three year old girl in a crosswalk this year. The driver didn't even get so much as a ticket. If there's some cop standing around with nothing to do I'm sure they could be assigned to look into the fifty pedestrian injury collisions that happen every day in New York.

>> "If there's some cop standing around with nothing to do..."

Honestly, I have (almost) only ever seen NYPD officers standing around with nothing to do. I don't know if that's because they are drastically overmanned or because they intentionally deploy loafing cops for the deterrent effect.

"Walking the beat" in the UK.

It is what uniformed police officers are supposed to do in popular imagination. Many in evidence in most UK cities in the run up to Xmas.