It took a few months, but Democratic Sen. Ron Wyden of Oregon finally got his answer from national intelligence chief James Clapper. Yes, Clapper wrote in a letter, the NSA does indeed spy on Americans' emails and phone calls—without a warrant—thanks to a revision in a law originally intended to apply only to foreigners, reports the National Journal. The existence of what Wyden has called a "back door" in the law first surfaced in August, courtesy of Edward Snowden, but Clapper didn't respond to Wyden's questions about it in January until the letter dated March 28. "This is unacceptable. It raises serious constitutional questions, and poses a real threat to the privacy rights of law-abiding Americans," wrote Wyden and Sen. Mark Udall.
"If a government agency thinks that a particular American is engaged in terrorism or espionage, the Fourth Amendment requires that the government secure a warrant or emergency authorization before monitoring his or her communications," they wrote. "This fact should be beyond dispute." The loophole stems from the 2008 FISA Amendments Act, which gives the government the right to intercept phone calls and emails on domestic soil, without a warrant, as long as the target lives abroad and isn't a citizen, explains the New York Times. In 2011, the government got permission from the Foreign Intelligence Surveillance Court to use the database to search for Americans' details, too. It's this "back door" that has led to most of the NSA's most controversial information-gathering programs, including PRISM, notes the Guardian.