The extent of a Department of Homeland Security program that allows customs officials to search and seize portable electronic equipment needs to be clearly defined. A recent Senate hearing on federal power to search electronic devices without cause should lead to greater transparency in and oversight of the practice.

Some travelers who have had their laptops inspected and confiscated, along with digital media cards, portable storage drives, BlackBerries and memory cards from digital cameras, have initiated lawsuits against the government over privacy concerns.

A suit from more than 20 cases involving laptops or other electronics seized at airports from mostly individuals with Muslim, Middle Eastern or South Asian backgrounds resulted in an appellate ruling upholding the government's authority to conduct those searches in the same way it would inspect a briefcase. But travelers argue legitimately that it could invite serious private security breaches.

Plaintiffs and congressional investigators suspect that digital copies are sometimes made of materials after they are seized at airports. If that's true, what happens to the information, which may contain sensitive business, legal, medical or personal data?

Customs officials refused to answer that question or even how common an electronics search and seizure is. If this program is going to continue, it needs not only distinct parameters but also proof that it's actually needed.