Without public debate, the federal government recently revoked a two-decade-old policy that limited the ability of customs agents to read and copy documents travelers bring into and out of America, according to newly released memoranda from the Department of Homeland Security.

The disclosure could fuel efforts already underway in Congress to rein in the virtually unfettered authority the federal government has claimed to read and copy the contents of laptop computers and electronic devices that tens of thousands of people carry into the country each day through airports and land borders.

The records, obtained under the Freedom of Information Act, show that a directive issued by the Customs Service in 1986 warned agents against reading travelers’ personal papers. “As a general rule, customs officers should not read personal correspondence contained in passengers’ baggage or on the person,” the policy said. Agents could “scan” documents for evidence of illegal activity or other connection to a customs-related issue, but could only copy the documents if there was probable cause to seize them, the directive said. A revision of the policy in 2000 said “as opposed to reading content, agents could glance at documents,” but needed a reasonable suspicion to hold onto the papers temporarily.

However, last year and this summer, the Department of Homeland Security loosened some of those standards and eliminated others. An interim internal policy issued in 2007 said customs agents could review and analyze the contents of documents and electronic devices “without individualized suspicion.” The probable cause standard for copying information was apparently dropped and replaced with a lower “reasonable suspicion” standard. In cases where agents needed help from another agency, no particular suspicion was required.

“The decision to change some of the standards in those older policies reflects the reality of the post-9/11 environment,” a spokeswoman for the department, Amy Kudwa, said yesterday. “These policies have always reflected that officers have the constitutional authority to inspect information present at the border without individualized suspicion.”

Ms. Kudwa also noted that the changes followed the passage in 2002 of legislation transferring customs inspections to the newly created Department of Homeland Security. However, she had no explanation for why the policy changes appear not to have taken place until 2007, almost six years after the strikes on America.

The records were released in response to a lawsuit filed by two civil liberties groups, the Asian Law Caucus and the Electronic Frontier Foundation.

In recent months, searches of laptops by customs agents have sparked concern from business travelers, lawyers who handle client information, and travelers of South Asian and Arab descent, who have claimed to be frequent targets for intrusive searches.

The department’s claim that it can rummage through any computer, BlackBerry, or digital camera crossing the border for virtually any reason has been met with alarm by some lawmakers.

“I was really, really outraged,” a congressman who represents parts of the Bronx, Westchester, and Rockland Counties, Eliot Engel, told The New York Sun last week. “It was called to my attention that people could just be searched essentially at the will or on the whim of whoever was searching them. There did not have to be probable cause. There did not have to be any suspicion.”

Mr. Engel said he was particularly disturbed to learn that some customs agents had demanded that travelers turn over their passwords for computers that were locked or encrypted. “It’s important that we have security in the fight against terrorism. … On the other hand, it’s really appalling that people could be forced to turn over private codes and private things if there’s not justification or reason or suspicion,” he said.

In late July, Mr. Engel introduced a bill that would require that agents have “reasonable suspicion” about an individual before searching personal electronics. The legislation would also require that the official searching be trained and conduct the search in private, if a traveler so requests.

Courts have ruled that computers coming across the border are no different than suitcases or crates of goods, which can be opened by customs authorities without a warrant or any specific grounds for concern. “It’s a preposterous analogy,” Mr. Engel said. He said he picked up a Republican cosponsor for the bill, Rep. Ron Paul of Texas, moments before it was introduced. “He read it right on the House floor and said, ‘Put me on,'” Mr. Engel said.

The Sun published a front-page story about the practice in June and other newspapers soon followed. An aide to Mr. Engel said his staff saw the Sun report. “I know the people in New York who read these papers definitely did,” the aide said.

Another Homeland Security spokeswoman, Laura Keener, said she was prohibited by department policy from commenting on pending legislation, but that administration officials are concerned about anything that would complicate the work of customs agents.

“We need to make sure our law enforcement personnel are not tied. They need to be able to do their job effectively,” she said.

In an interview last month, Secretary of Homeland Security Chertoff said he published the most recent policy to assure business travelers they do not face suspicionless searches. “That’s exactly why I put it up on the Internet,” he told Wired.com. “We only do it when we put you into secondary and we only put you into secondary when there is a suspicion, when there is a reason to suspect something.”

A lawmaker who called a hearing on the subject in June, Senator Feingold of Wisconsin, took issue with Mr. Chertoff’s comments. “The policy that DHS published … says the exact opposite: it contains no mention of secondary screening, and it expressly states that Americans’ laptops may be searched ‘absent individualized suspicion,'” the senator said in a statement e-mailed to the Sun.

Mr. Feingold, a Democrat, called the secretary’s comments “factually inaccurate” and said they bred confusion. “The fact that Secretary Chertoff’s description of DHS’s published policy differs so starkly from the policy itself underscores the need for Congress to act in order to protect law-abiding Americans against these highly intrusive searches,” the senator said.

Ms. Keener denied any disparity between Mr. Chertoff’s comments and the published rules. “They’re not incongruous,” she said. “He’s saying, in most cases, there is some type of suspicion or suspicious activity that would warrant … a second look.”

So far, the Engel-Paul bill has six additional cosponsors, including two New York Democrats, Reps. Nita Lowey and Maurice Hinchey. Rep. Zoe Lofgren of California, another Democrat, filed a similar bill a week before Mr. Engel, but no other lawmaker has signed on to that measure. Mr. Feingold is expected to weigh in shortly with his own legislation, but it seems doubtful that any of the bills will advance this year.