In the wake of the shooting of a Nazi officer, Police Capt. Louis Renault played by Claude Rains in the 1942 movie "Casablanca," ordered his men to "round up the usual suspects." Was Renault engaging in some sort of profiling? He may have been, but what is profiling? Let's look at it.
We can think of profiling as a method to economize on information costs by using easily observed physical characteristics as a proxy for some other characteristic more difficult or costlier to observe. For example, say you seek to hire people to manually unload trucks containing heavy merchandise. I'm guessing that most would use sex as a proxy for strength and select men over the women. That can be called sex profiling. Of course, if you assumed that men and women have equal strength, you'd hire randomly.
You might say, "Profiling is unfair, and individuals should be judged individually!" Taken to the limit, such a position is ludicrous. Suppose police are trying to catch the criminal who just raped a woman in a city park. Would you want them to use sex profiling -- i.e., just round up men -- or should they round up everyone, regardless of sex? I'm betting that most people would view the latter as stupid. But there is a near equivalent in government. Ninety-six percent of the FBI's list of most wanted terrorists are Muslim, and most terrorist attacks in the U.S. have been committed by young Muslim males. Despite this, the Transportation Security Administration people behave as if each person who seeks to board a plane is of equal danger. That's why they search, frighten and inconvenience 5-year-olds and elderly people.
Some racial and ethnic groups have higher incidence of -- and mortality from -- various diseases than the national average. The Pima Indians of Arizona have the world's highest diabetes rates. Black males have the highest incidence rate for prostate cancer in the United States. Black males are also 30 percent likelier to die from heart disease than white men. Laotian, Samoan, and Vietnamese women have the highest cervical cancer rates in the United States.