He didn’t get sick or have something better to do. Hell, he didn’t even miss a flight. Instead, according to Schneier, the TSA itself had him removed from the panel:
On Friday, at the request of the TSA, I was removed from the witness list. 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.
As Tim Lee notes in reporting on this story, the TSA has done similar things in the past, and even been rebuked by Rep. Jason Chaffetz — and yet it had no problem doing it again. The fact that Schneier is a part of that lawsuit is meaningless and shouldn’t stop him from testifying at all. Schneier is a clear thorn in the side of the TSA, and if it’s so afraid of having him speak to Congress, that really says a lot about the (lack of) confidence it has in its own arguments. If you can’t stand to let a critic speak, it suggests that perhaps your own argument isn’t very strong.