In the meantime, the customs agency publicly released its policies on border searches in July, including a statement that agents are authorized to "read and analyze" any documents in a traveler's possession and keep them for a reasonable time to make copies.
What the agency didn't announce - but what the documents obtained in the lawsuits reveal - is that the current practices represent a substantial change from earlier government policies, Sinnar said.
She said those policies were first enacted by President Ronald Reagan's administration in 1986, in response to lawsuits by U.S. citizens who were questioned and searched after returning from Nicaragua. President Bill Clinton's administration refined the policies in 2000 but made no major changes, Sinnar said.
Those policies allowed customs agents to glance at travelers' documents to see if they contained anything the agents were authorized to intercept - such as smuggled currency or obscene material - but required agents to have grounds for reasonable suspicion before taking and reading any documents, the legal groups said, quoting the newly released records.
The 1986 and 2000 policies required agents to meet a more-demanding standard - showing evidence that contained probable cause of smuggling or other wrongdoing - before copying documents, the lawyers' groups said.
"For more than 20 years, the government implicitly recognized that reading and copying the letters, diaries, and personal papers of travelers without reason would chill Americans' right to free speech and free expression," Sinnar said. "But now customs officials can probe into the thoughts and lives of ordinary travelers without any suspicion at all."
