One item that could be getting left on the table as the 116th Congress comes to a close is a reauthorization of surveillance authorities. But, how did we get here?

The Patriot Act — enacted after the Sept. 11 attacks in order to bolster law enforcement powers to fight terrorism — was well-supported at the time. However, the act and its Section 215 became controversial after the Edward Snowden leaks revealed the National Security Agency had collected millions of American’s phone records and a new version of the law was passed in 2015. That lapsed in March and Congress never approved its reauthorization amid spats between chambers and a presidential veto threat.

Watch as CQ Roll Call breaks down Section 215 and explains how we got here.

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