Drug deals and other crimes sometimes take place in public restrooms. May the police look into a restroom stall to observe a crime being committed?
The invasion of privacy in a public restroom goes beyond simply peeking into stalls; there are many people who use restrooms for their intended purpose and nothing more. For law enforcement to be able to search or roust a restroom, there needs to be reasonable suspicion: some form of evidence that (1) a crime has been committed, (2) a crime is being committed, or (3) a crime will be committed. Each of these situations has different outcomes: for (1), a CSI sweep for evidence; for (2) an invasion of privacy to arrest criminals and hopefully prevent further crimes; for (3) possibly a stakeout or cameras, which would be very invasive, and in my opinion would need a lot more justification.
I don't think that a person in this case would have a reasonable expectation to privacy. I don't see how doing something illegal in a public bathroom is any dfifferent from being on the street corner or in a store. Police do have to have a warrant to search a citizen's private property. Other than that, if you are in public your privacy is extremely minimal.
I think that in the context presented, the person might expect to have a reasonable expectation of privacy of their own person. Yet, the fact that it is a public restroom minimizes the expectation of privacy extending anything beyond that. The public aspect of the restroom is an example of how the purest form of individual rights is minimized in a public setting. This might not be a post 9/11 perspective as much as something embedded in the Constitution by the framers. As committed as they were to the notion of individual rights, they also understood the idea of the social contract as advocated by thinkers like John Locke. Such an idea suggested that individuals understand the need that issues of privacy are not meant to come at the cost of public safety and other concerns. If the search for drugs is deemed as a public concern that warrants the involvement of the police officers, then their compulsion to serve the ends of public safety overrides much in way of claims that suspects in a public restroom might claim in the search and seizure of narcotics. If there is probable cause and reason enough for the police officers to investigate the potential for criminal activity in the restroom, then this right to public safety can override a claim to privacy if it is used as a shield for criminal activity.
Again, context is important. Can the police simply based upon the idea that crime occurs in public restrooms peer willy-nilly into a closed stall?
No. More is needed. These types of questions turn upon what the courts refer to as the "totality of the circumstances", that is what a "reasonable officer" in that place, observing what he sees, knowing what he knows at that moment and as interpreted thru his training and experience believes is happening.