In the post above this one, I discuss the fact that criminal cases are sometimes rejected due to bad police searches. This doesn’t necessarily mean that the police are arbitrarily disregarding people’s rights.
Many people think it’s all very simple: there are clear lines, the police know what they are, and they simply choose to cross the line on a routine basis.
I don’t think that’s the case.
Most of the time, when a search is “bad,” police believed that the search was “good.” In my experience, the police generally try to stay within the bounds of the Constitution. But Fourth Amendment law is very complex, with all sorts of arbitrary lines. Sure, you can search the car, but can you search the container inside the car? Can you search the trunk? Can you search containers in the trunk? Can you order a passenger out of the car? Can you pat her down? Can you reach into her pockets? Can you search the passenger’s handbag? Does it matter whether she left it in the car, or still has it on her shoulder when she exits?
There are answers to most of these questions, and police officers are trained on these issues. But they aren’t lawyers, and situations come up that aren’t clearly covered by what they’re taught in class. Lawyers can sit in their chairs, pull a book off a shelf or punch a case up on a computer, and determine whether a judge is likely to toss this case based on a particular set of facts. But even we must sometimes resort to the books.
A cop in the field doesn’t have that luxury. He has to make a decision: can he take this action or not?
If he makes the wrong decision, on a case where I would have had to look up the answer in a book, that doesn’t make him a bad cop.