Investigators don't have to suspect illegal activity in order to read people's e-mail, examine their photographs, and find out what Web sites they have visited when they enter the United States with laptops or other electronic devices, the U.S. Department of Homeland Security said recently.

DHS outlined its policies on searching information contained in personal electronics last month. The release of information was in response to public interest in the matter. The courts recently upheld the federal government's right to search laptops and other electronic devices to combat terrorism, child pornography, and other crime.

Border agents can examine the contents of laptops and other devices of citizens and foreigners entering the United States, without suspicion of criminal wrongdoing -- as long as they return them in a reasonable amount of time, according to DHS and the courts. The government and the courts have not defined what constitutes reasonable.

Critics contend that the practice is a violation of privacy and that it compromises trade secrets and other sensitive information contained in the laptops of traveling professionals.

DHS said the information or copies of it can be examined on or off site, but it can only be retained if investigators have reasonable suspicion of unlawful activity or if the information relates to immigration matters.

The policy states that border agents must treat business or commercial information as confidential and "take all reasonable measures to protect that information from unauthorized disclosure." The document states that some information may be protected by the Trade Secrets Act and other privacy laws.

DHS also said that some information may be covered by attorney-client privilege. The policy is vague about the privilege and states that such information isn't necessarily exempt from searches but may require "special handling procedures." It advises agents to seek advice from top legal counsel if a document may "constitute evidence of a crime or otherwise pertain to a determination within the jurisdiction" of custom agents.

The DHS document does not address medical issues and documents, which generally fall under stricter privacy protections than other information.

U.S. Sen. Russell Feingold, D-Wis., said he plans to introduce legislation limiting such searches.

Editor's Note: This story was updated on Aug. 6 to more accurately describe DHS' policy on retaining information from laptops.