The U.S. Department of Homeland Security has concocted a remarkable new policy: It reserves the right to seize for an indefinite period of time laptops taken across the border.

A pair of DHS policies from last month say that customs agents can routinely–as a matter propecia blood pressure of course–seize, make copies of, and "analyze the information transported by any individual attempting to enter, re-enter, depart, pass through, or reside in the United States." (See policy No. 1 and No. 2.)

DHS claims the border search of electronic information is useful to detect terrorists, drug smugglers, and people violating "copyright or trademark laws." (Readers: Are you sure your iPod and laptop have absolutely no illicitly downloaded songs? You might be guilty of a felony.)

This is a disturbing new policy, and should convince anyone taking a laptop across a border to use encryption to thwart DHS snoops. Encrypt your laptop, with full disk encryption if possible, and power it down before you go through customs.

Here's a guide to customs-proofing your laptop that we published in March.

It's true that any reasonable person would probably agree that Customs agents should be able to inspect travelers' bags for contraband. But seizing a laptop and copying its hard drive is uniquely invasive–and should only be done if there's a good reason.

Sen. Russell Feingold, a Wisconsin Democrat, called the DHS policies "truly alarming" and told the Washington Post that he plans to introduce a bill that would require reasonable suspicion for border searches.

But unless Congress changes the law, DHS may be able to get away with its new rules. A U.S. federal appeals court has ruled that an in-depth analysis of a laptop's hard drive using the EnCase forensics software "was permissible without probable cause or a warrant under the border search doctrine."

At a Senate hearing in June, Larry Cunningham, a New York prosecutor who is now a law professor, defended laptop searches–but not necessarily seizures–as perfectly permissible. Preventing customs agents from searching laptops "would open a vulnerability in our border by providing criminals and terrorists with a means to smuggle child pornography or other dangerous and illegal computer files into the country," Cunningham said.

The new DHS policies say that customs agents can, "absent individualized suspicion," seize electronic gear: "Documents and electronic media, or copies thereof, may be detained for further review, either on-site at the place of detention or at an off-site location, including a location associated with a demand for assistance from an outside agency or entity."

Outside entity presumably refers to government contractors, the FBI, and National Security Agency, which can also be asked to provide "decryption assistance." Seized information will supposedly be destroyed unless customs claims there's a good reason to keep it.

An electronic device is defined as "any device capable of storing information in digital or analog form" including hard drives, compact discs, DVDs, flash drives, portable music players, cell phones, pagers, beepers, and videotapes.