The question as phrased assumes that the primary incentive for joining the police is impunity for casual lawlessness. That's dystopian. You could also ask the

The question as phrased assumes that the primary incentive for joining the police is impunity for casual lawlessness. That's dystopian. You could also ask the same question of skilled martial artists and armed forces veterans. Both classes can face higher penalties, but that doesn't deter people from becoming Army Rangers or karate black belts.