WASHINGTON - President Barack Obama has chosen Joseph Clancy as the new head of the U.S. Secret Service, the White House said on Wednesday, after a series of high profile security lapses led to a shake-up in the troubled agency's leadership.

Clancy, who personally helped guard the lives of three U.S. presidents, has been head of the agency on an interim basis for the past four months. Director Julia Pierson stepped down in October after an embarrassing Sept. 19 White House breach in which a man carrying a knife jumped the fence and ran into the executive mansion.

Obama chose Clancy, a 27-year veteran of the Secret Service, despite the recommendation of an independent review panel in December that the next director be someone from outside the agency, which it said had become too insular.

White House spokesman Josh Earnest said Clancy has "a lot of credibility built up inside the agency and he used that credibility to put in place reforms that were recommended by this outside panel" appointed by Homeland Security Secretary Jeh Johnson.

"Over the course of the last several months, Director Clancy has demonstrated the kind of leadership that frankly many of us expected him to demonstrate," Earnest said at a news briefing. Republican U.S. Representative Jason Chaffetz, chairman of the House Oversight and Government Reform Committee, which has investigated the Secret Service's problems, said he was disappointed Obama did not appoint someone with a fresh perspective.

"The good men and women of the Secret Service are screaming for a fresh start," he said in a statement. "At this moment in time, the Secret Service would best be served by a transformative and dynamic leader from outside the agency."

Clancy rejoined the service after leaving his job as head of security for the Comcast media corporation in the Philadelphia area where he grew up.

In addition to the fence-jumper with a knife in September, the service's credibility also was damaged in 2012 when it was revealed that members had hired prostitutes while in Cartagena, Colombia, in advance of an Obama trip and in 2011 when a man hit the White House with automatic rifle fire, although the damage was not discovered until four days later.