Ann de Wulf

Bruce Schneier, a vocal critic of security measures used by the Transportation Security Administration, was asked to testify before Congress about TSA's security screening initiatives but then was "formally uninvited" after the agency complained.

"On Friday, at the request of the TSA, I was removed from the witness list," Schneier wrote on his blog. "The excuse was that I am involved in a lawsuit against the TSA, trying to get them to suspend their full-body scanner program. But it's pretty clear that the TSA is afraid of public testimony on the topic, and especially of being challenged in front of Congress. They want to control the story, and it's easier for them to do that if I'm not sitting next to them pointing out all the holes in their position. Unfortunately, the committee went along with them."

A TSA spokeswoman told CNET she would look into the matter but did not immediately have comment this afternoon.

The House Committee on Oversight and Government Report, which had invited Schneier a few weeks ago to testify at today's hearing, told Schneier that committee staffers would try to invite him back for another hearing, he said. But Schneier said he was not sure that his busy schedule would permit him to appear and said it would have been much more effective for him to be able to ask the TSA questions directly during a hearing.

"I'm there in spirit, though. The title of the hearing is "TSA Oversight Part III: Effective Security or Security Theater?" he said, referring to " security theater ," the phrase he coined that describes security measures that make officials feel like their practices are making people more secure but which are in fact largely ineffective.

It's not the first odd behavior involving the TSA and congressional hearings related to its security policies and procedures. The TSA backed out of a hearing on its full-body scanners a year ago at the last minute, complaining that agency representatives were to be seated next to someone from the Electronic Privacy Information Center (EPIC), which is behind the lawsuit against the TSA over the scanners, according to CNS News.com. TSA representatives changed their mind and showed up late.

Update March 27 at 1 p.m. PT: A TSA spokeswoman told CNET that the agency had no comment.