Police fire tear gas from an armored personnel carrier on Aug. 18 in Ferguson, Mo. The U.S. Senate is holding a hearing on the use of military-grade equipment by local police departments. Jeff Roberson/AP hide caption

itoggle caption Jeff Roberson/AP

Page County, Va., Sheriff John Thomas received an MRAP for his department in May. "Is it overkill? Yeah, it is. I mean, for our use, it's more armor than we need. But it's free," he says. David Welna/NPR hide caption

itoggle caption David Welna/NPR

Members of the House of Representatives leave after a procedural vote on Capitol Hill in Washington on Friday, as Republicans reshaped legislation to deal with the border crisis, a day after Congress was supposed to go into its August recess. J. Scott Applewhite/AP hide caption

itoggle caption J. Scott Applewhite/AP

Immigrants run to jump on a train in Ixtepec, Mexico, during their journey toward the U.S.-Mexico border. President Obama wants nearly $4 billion in emergency funds to deal with the tens of thousands of children from Central America who've been crossing the border. Eduardo Verdugo/AP hide caption

itoggle caption Eduardo Verdugo/AP

Director of National Intelligence James Clapper (center), accompanied by FBI Director Robert Mueller (left) and CIA Director John Brennan, testifies on Capitol Hill on March 12, 2013. When questioned, Clapper said the NSA did not collect data on Americans. He later acknowledged his response was "clearly erroneous." Susan Walsh/AP hide caption

itoggle caption Susan Walsh/AP

Over the last dozen years, whistleblowers at the National Security Agency have had a rough track record, facing FBI raids and lawsuits. NSA/Reuters/Landov hide caption

itoggle caption NSA/Reuters/Landov