Who do you report a security screener to at the airport that acted inappropriately?

Here are the basics: My friend has been harassed and stalked by this guy who knows her. This has been going on for awhile now. He ran into at the mall just yesterday and told her he saw her car and knows what she drives now. Anyway, she is flying in to see me today from out of state and he works as a screener at the security line at the airport. He flagged her and said he knew her and she was a trouble maker and was the "anti-christ" and he had reason to believe she "might have a bomb or something". He had her pulled out of line, wanded and her things searched. He even had them take a swab from her mouth! I have never even heard of that. Surely that part is something that is done only if there is a serious situation like supicious behavior. He's done this before. The supervisor blew her off and said they were too busy and she'd "talk to him". He clearly abused his authority and has a history of harassing her. Where/how do we go to go over the supervisor's head to report this?

Well,you may not beleive this but everyone DOES answer to somebody. Contact the Department of Transportation or Homeland Security.
Look in your phone book under U.S. Government and see if they're listed. If not,look up Office of U.S. Inspector General .
If you should find any of these,make contact in person and ask to speak to an investigator and explain in detail along with date(s) . Good luck.

They are allowed to do pretty much whatever they want. The way it works is if you complain you get yourself on a list and then you'll really find out what it's like to be searched.

It doesn't sound to me like he overstepped his authority, although of course what he did was wrong. It's just that being wrong is his job.