SAN FRANCISCO – Jim Harper left his hotel early Thursday at 5:30 a.m. to give himself more than two hours to clear security at San Francisco International Airport. It wasn't that he was worried the security line would be long, but because he accepted a dare from civil liberties rabble-rouser John Gilmore to test whether he could actually fly without showing identification.

Gilmore issued the challenge at Wednesday's meeting of the Department of Homeland Security's privacy advisory committee in San Francisco, which otherwise lacked much in the way of controversy. An entrepreneur and co-founder of the Electronic Frontier Foundation, Gilmore recently lost a court battle seeking to unmask the government's secret regulations asking passengers to show identification when flying, and to have those rules declared unconstitutional.

Scolding the DHS committee for dithering over small matters, Gilmore said that it should be investigating the National Security Agency's eavesdropping program and that the committee's real job was to "protect the homeland from mean-spirited officials."

Gilmore then dared committee members to place their driver's licenses in the envelopes he had passed out, mail them to their home addresses and then attempt to fly home without identification.

While signs in the airport and on the Transportation Security Administration website insist that showing ID is mandatory, the official policy, as revealed by the judges' decision (.pdf) in Gilmore's case, is that "airline passengers either present identification or be subjected to a more extensive search." But Gilmore said that's not what really happens in an airport when one refuses to provide identification.

"You will find out what the real rules are," Gilmore said. "Are you afraid to? You have good reason."

Gilmore referred to his own experience when Southwest Airlines refused to let him fly in 2002 without identification, and a recent blog post by travel expert Edward Hasbrouck, chronicling his near-arrest for trying to figure out if the person checking identification at Washington Dulles International Airport was an airline or federal employee.

At the meeting's close, Harper, a committee member, said he'd take the challenge so long as he could hand his envelope to a reporter who accompanied him to the airport. He also challenged the other members to join him.

"We have influence," Harper said. "I challenge my colleagues to believe in the law."

None of the other committee members volunteered, but the committee's chair, former director of consumer protection for the Federal Trade Commission Howard Beales gave Harper a tongue-in-cheek blessing.

"I wish Jim the best and hope to see you in the future," Beales said.

At 6 a.m. the next morning, Harper handed this reporter a green, self-addressed stamped envelope and entered the checkpoint line, which even at that early hour was filled with travelers facing a 20-minute crawl to the magnetometers.

Harper told the identification checker he had no ID, and the attendant quickly wrote "No ID" with a red marker on his ticket and shunted him off to an extra screening line – generously allowing him to bypass the longer queue of card-carrying passengers.

There Harper was directed into the belly of a General Electric EntryScan puffer machine that shot bits of air at his suit in order to see if he had been handling explosives.

TSA employees wearing baby blue surgical gloves then swiped his Sidekick and his laptop for traces of explosives and searched through his carry-on, while a supervisor took his ticket, conferred with other employees and made a phone call.

Meanwhile, a TSA employee approached this reporter, who was watching the search through Plexiglas, and said, "It's pretty awkward you are standing here taking notes," but he did not ask for identification or call for a halt to the note-taking.

The TSA supervisor returned from her phone call and asked Harper why he didn't have identification and to where he was traveling. But she was satisfied enough with his answer – that he had mailed his driver's license home to Washington, D.C. – that she allowed him to pass.

At 6:30 a.m., standing 50 yards away on the other side of the glass screen, Harper phoned to say he now had two hours to kill, having gotten through screening perhaps even faster than he would have if he'd shown ID. He guessed he was able to get through without much hassle by being polite and dressing well.

Why did he take the challenge?

"Part of it was my concern with the growing use of identification checks to control access to society, such as buildings, stadiums and air travel," Harper said, referring to issues that are central to his recently published book, Identity Crisis.

And will he do it again?

"Yeah, I'm inclined to do it more and more and hopefully more people will follow my lead and it will become a clear option to not show government ID to fly," Harper said. "My identity has nothing to do with the real risk.

"In fact, today, I'm the safest guy on the plane."