No, poor pay in no way justifies lawlessness in the uniform - but if the police were actually held to the law, most of them would be in prison in short order and the people that we really want to take their place will be somewhere else, making more money and dealing with less stress.
Poor pay?? I will never understand why this misconception cannot be stamped out. That concept was true decades ago, but not today. Many Miami Police Beach Patrol Officers make well over $100K.
The reason that every major university maintains a department of mathematics is that it's cheaper than institutionalizing all those people.