Password-protected rights?

It's Monday, so it must be Adam Liptak day (until the 15th, when his columns move to Tuesday).

Better make sure your files are encrypted if you plan to cross the border with anything on your laptop you'd rather not share with the U.S. government.

It is true that the government should have great leeway in searching physical objects at the border. But the law requires a little more — a “reasonable suspicion” — when the search is especially invasive, as when the human body is involved.

Searching a computer, said Jennifer M. Chacón, a law professor at the University of California, Davis, “is fairly intrusive.” Like searches of the body, she said, such “an invasive search should require reasonable suspicion.”

An interesting supporting brief filed in the Arnold case by the Association of Corporate Travel Executives and the Electronic Frontier Foundation said there have to be some limits on the government’s ability to acquire information.

“Under the government’s reasoning,” the brief said, “border authorities could systematically collect all of the information contained on every laptop computer, BlackBerry and other electronic device carried across our national borders by every traveler, American or foreign.” That is, the brief said, “simply electronic surveillance after the fact.”

The government went even further in the case of Sebastien Boucher, a Canadian who lives in New Hampshire. Mr. Boucher crossed the Canadian border by car about a year ago, and a customs agent noticed a laptop in the back seat.

Asked whether he had child pornography on his laptop, Mr. Boucher said he was not sure. He said he downloaded a lot of pornography but deleted child pornography when he found it.

Some of the files on Mr. Boucher’s computer were encrypted using a program called Pretty Good Privacy, and Mr. Boucher helped the agent look at them, apparently by entering an encryption code. The agent said he saw lots of revolting pornography involving children.

The government seized the laptop. But when it tried to open the encrypted files again, it could not. A grand jury instructed Mr. Boucher to provide the password.

But a federal magistrate judge quashed that subpoena in November, saying that requiring Mr. Boucher to provide it would violate his Fifth Amendment right against self-incrimination. Last week, the government appealed.

The magistrate judge, Jerome J. Niedermeier of Federal District Court in Burlington, Vt., used an analogy from Supreme Court precedent. It is one thing to require a defendant to surrender a key to a safe and another to make him reveal its combination.

Actually, this leads me to a question: anyone know of any good encryption programs for iBooks?