There are 2 policemen parked along a one-way street looking for traffic violations. They spot a taxi driver going in the wrong direction, yet they do nothing. Why?
How are they to chase the suspect? They couldn't follow the car becuase then they would be breaking the law (plus doing a u-turn in a 1-way street is pretty hard, unless they were originally parked the wrong way, which is also illegal). But I guess, they're policemen, so they were probably asleep or busy eating/drinking coffee...