A couple of years ago, Michael T. Arnold landed at the Los Angeles International Airport after a 20-hour flight from the Philippines. He had his laptop with him, and a customs officer took a look at what was on his hard drive. Clicking on folders called “Kodak pictures” and “Kodak memories,” the officer found child pornography.

The search was not unusual: the government contends that it is perfectly free to inspect every laptop that enters the country, whether or not there is anything suspicious about the computer or its owner. Rummaging through a computer’s hard drive, the government says, is no different than looking through a suitcase.

One federal appeals court has agreed, and a second seems ready to follow suit.

There is one lonely voice on the other side. In 2006, Judge Dean D. Pregerson of Federal District Court in Los Angeles suppressed the evidence against Mr. Arnold.

“Electronic storage devices function as an extension of our own memory,” Judge Pregerson wrote, in explaining why the government should not be allowed to inspect them without cause. “They are capable of storing our thoughts, ranging from the most whimsical to the most profound.”