In the last year, more than two dozen reporters across the country have been subpoenaed or questioned about their confidential sources in cases before federal courts, the Newspaper Association of America said.
Now, a Congressional inquiry is trying to determine who leaked covert CIA official Valerie Plame's name to the media in 2003.
"It does feel like open season," Laura Handman, a First Amendment lawyer based in Washington told The New York Times. "There are more instances of courts ordering confidential sources to be disclosed."
A special Senate counsel tried unsuccessfully to subpoena the reporters' telephone records to unmask their confidential source.