John Allen Paulos gives mathematical arguments against profiling, and why we should pass gun control laws instead.
He also gives legalistic constitutional arguments, where he is a little out of his field.
Security expert Bruce Schneier frequently gives arguments against profiling. Here he attacks the related idea of issued preferred IDs to certain airline passengers in the Trusted Traveler program.
These arguments are fallacious. I wonder how these guys think that law enforcement officials ever catch anyone, if they cannot make any tentative conclusions about who is suspicious.
One argument says that security, like a chain, is only as strong as its weakest link. So unless everyone is treated the same, the bad guys will just act like whomever is the least suspicious, and therefore minimize the chance of getting caught.
The flaw is that not all strategies are equally available to the bad guys. Some people are a lot easier to recruit for criminal acts than others.