A secret service agent stands before the arrival of U.S. President George W. Bush at Prestwick Airport July 6, 2005 in Prestwick, Scotland.
John Moore—Getty Images
WASHINGTON, DC - JANUARY 21: A Secret Service vehicle escorts President Barack Obama and First Lady Michelle Obama's motorcade during the inauguration parade on January 21, 2013 in Washington, DC. President Obama was ceremonially sworn in for a second term office during a public ceremony at the U.S. Capitol building. (Photo by John Moore/Getty Images)
United States Secret Service director Julia Pierson and Senate Homeland Security Committee Chairman Tom Carper, D-Del., leave a committee hearing on Secret Service agents behavior, on Capitol Hill in Washington, Tuesday, April 1, 2014.
The Washington Post—The Washington Post/Getty Images
Julia Pierson, director of the U.S. Secret Service, is grilled by members of congress during a Hearing by the House Oversight Committee on the flaws and errors by the U.S. Secret Service in protecting the White House held at the Rayburn House Office Building on Tuesday, September 30 , 2014, in Washington, DC.
US Secret Service / AP
This undated handout photo provided by the US Secret Service shows Secret Service agent Julia Pierson.
Larry Downing / REUTERS
U.S. President Barack Obama (R) shakes hands with U.S. Secret Service agent Julia Pierson (L) after she is sworn in as the first woman Director of the Secret Service by Vice President Joe Biden in the Oval Office of the White House in Washington, March 27, 2013.
Acting Secret Service Director Joseph Clancy testifies on Capitol Hill in Washington, in 2014.
Secret Service officers search the south grounds of the White House for an unmanned aerial drone in Washington D.C. on Jan. 26, 2015.
Uniformed Secret Service officers walk along the fence on the North side of the White House in Washington, Sept. 20, 2014.
A Secret Service agent watches the crowd as President Barrack Obama speaks in Holmdel, N.J. on July 16, 2009.
Pedro Mendoza / AP
The Hotel Caribe in Cartagena, Colombia, on April 19, 2012. The U.S. Secret Service scandal took place in the hotel earlier a few days earlier
SAMAD / AFP / Getty Images
A Secret Service agent guards his post on the roof of the White House as a lamp post is adorned with Chinese and U.S. national flags in Washington, D.C., on Jan. 17, 2011
Kevin Lamarque / Reuters
A Secret Service officer keeps people back as smoke billows from the Eisenhower Executive Office Buildings next to the White House in Washington, December 19, 2007.
U.S. Secret Service agent David Popp contrasts genuine dollar bills against the fakes.
Pablo Martinez Monsivais—AP
An Officer of Secret Service Uniform Division patrols the front of the White House, Feb. 26, 2015.
Uniformed Secret Service officers walk along the lawn on the North side of the White House in Washington on Sept. 20, 2014. The Secret Service is coming under renewed scrutiny after a man scaled the White House fence and made it all the way through the front door before he was apprehended.
Brendan Smialowski—AFP/Getty Images
Members of the Secret Service are seen on the roof the White House in Washington, Sept. 29, 2014.
Brendan Smilowski—AFP/Getty Images
Members of the US Secret Service arrive to escort President Barack Obama on a trip at Andrews Air Force Base on Oct. 1, 2014 in Maryland.
Carolyn Kaster / ASSOCIATED PRESS
A member of the United States Secret Service Uniformed Division and the United States Park Police stand inside a buffer zone to keep people away from the White House perimeter fence Sunday, Oct. 13, 2013, in Washington.
Mike Theiler / Reuters
The U.S. Secret Service delivered a new 2001 Cadillac limousine for President Clinton's use with only six days left in his administration, January 15, 2001.
EVAN VUCCI / AP
Vice President Cheney with a Secret Service agent at the White House Wednesday
“Cached in coffin, new member is inducted into club. Initiate: Thomas J. Callaghan, head of Chicago district of U.S. Secret Service. Horseshoe waver: General Lorenzen.”
"Cached in coffin, new member is inducted into club. Initiate: Thomas J. Callaghan, head of Chicago district of U.S. Secret Service. Horseshoe waver: General Lorenzen."
President Barack Obama, during his candidacy in 2008, is surrounded by Secret Service agents as he boards an elevator at his hotel in Berlin, July 24, 2008.