While cameras were focused on DACA Tuesday, another Congressional battle was playing out but with much less attention.

Five senators, three Democrats and two Republicans, tried to filibuster the reauthorization of FISA Amendments Reauthorization Act of 2017.

FISA is the Foreign Intelligence Surveillance Act, originally written in 1978. It was updated in 2008 with Section 702 - the part filibustering senators were particularly concerned with.

Section 702 allows United States intelligence agencies to spy on any foreigner outside the U.S. without a warrant.

The filibuster ultimately failed, though, to the disappointment of civil liberties groups and a full vote on the bill is expected next week.

Professor Robert F. Turner explains Section 702 and the controversy surrounding its reauthorization.

Turner is the co-founder of the University of Virginia Law School’s Center for National Security Law.