A September incident in which a fence jumper made it deep into the White House was one of a series of recent public embarrassments for the Secret Service. (Mandel Ngan/AFP/Getty Images)

Joseph Clancy, who became acting director of the Secret Service last month following a string of security missteps, plans to tell lawmakers Wednesday that his storied agency has “fallen short” of its high standards and that recent public attention has had “detrimental effects on workforce morale and operational security, both with potentially dire consequences,” according to a copy of his prepared remarks.

In testimony submitted to the House Judiciary Committee and made public late Tuesday, Clancy describes an agency that has come under increasing pressure from an expanded portfolio in the years since the Sept. 11, 2001, terrorist attacks and is now stretched thin.

Clancy, the former head of President Obama’s security detail who came out of retirement following the abrupt resignation of Director Julia Pierson, says he is conducting a “comprehensive, bottom-to-top assessment” to determine the “root cause” of the recent missteps, including holding town-hall meetings with employees and spending time at the White House complex with agents and officers.

Clancy pointed to a number of security breaches that have received particular attention.

He describes an “unacceptable,” days-long delay between a November 2011 shooting and the discovery of bullet damage to the White House residence, saying the agency has adopted a “systematic process” to search the complex after any shootings in the area.

Joseph Clancy with President Obama in March 2010. (Pool photo by Mike Theiler/European Pressphoto Agency)

Clancy calls “simply inexcusable” a Sept. 19 incident in which a fence jumper was able to get inside the White House.

And Clancy says the agency has concluded that a “lack of due diligence on the part of advance team members” allowed an armed private security contractor to get on an elevator with the president during his Sept. 16 visit to Atlanta. Clancy says the violation of the agency’s security protocols was serious and remains under review. He says Secret Service headquarters has moved to correct the problem by providing more instructions and “written procedures to clarify and reinforce existing policies regarding armed contractors in proximity to the President to prevent similar incidents.”

“I want to assure you and the public that the past incidents are not treated lightly and do not come without positive change,” he says in the written testimony.

Clancy says that the recent mistakes “suggest that while we strive for perfection, we have, on limited occasions, fallen short of that goal.”

He adds, “Instead of remaining the organization that prides itself on operating silently and courageously behind the scenes, we are now in the public spotlight.”

Clancy’s testimony, along with the questions he will answer Wednesday from House members, represent the first public pronouncements the acting director has made about the agency’s security lapses and broader challenges since Pierson resigned and Obama asked him to take over temporarily.

Lawmakers in both parties said they lacked confidence in Pierson, whose resignation followed a tense and halting appearance before a House committee on Sept. 30.

While members of Congress complained that Pierson seemed unable to acknowledge the deep-rooted problems within her agency, Clancy has been seen as a more credible leader for the agency. He has the “very deep trust” of the Obamas, said Rep. Elijah E. Cummings (D-Md.), as a result of Clancy’s time leading the president’s protective detail during his first two years in office.

Rep. Bob Goodlatte (R-Va.), who chairs the Judiciary Committee, said last week that he was “anxious to get to the bottom of these problems at the agency so that we prevent such security lapses from happening again in the future.”

In his written testimony, Clancy says agents and officers have been struggling for years with an ever-expanding mission, with not enough people to do the job.

Clancy notes that in the wake of the 2001 terrorist attacks, the Secret Service took on the responsibility of security for large public events that could be the target of terrorists, including summits that involve multiple heads of state, as well as political conventions and the Olympics.

He says the agency provides physical protection or full-time protective details to 27 people, including the president, the vice president, the first family, former presidents and other top government officials. In fiscal 2014, its agents and officers provided security and protective plans for 5,700 individual visits, or “stops,” during political leaders’ domestic trips and 390 stops on international trips, Clancy says.

He says the public is not able to see the countless times they have done their jobs flawlessly.

“Our workforce, even as it has decreased in recent years, has risen to meet the challenges of these growing demands,” he says. “It has not been easy for them.”

Still, Clancy’s statements echo the fears that Cummings and others shared last month that something must be very wrong with the Secret Service leadership, given that so many of its current and former employees have been reaching out to the media and lawmakers to express concerns about lapses and failings.

The Washington Post has reported on several incidents of security breaches, including the 2011 shooting at the White House and the fumbled investigation, as well as the fact that fence jumper Omar J. Gonzalez was able to race through much of the main floor of the White House before being tackled by an off-duty officer.

“I share the concerns expressed by many members of Congress that some employees are more comfortable speaking with people outside the agency than they are with their supervisors,” Clancy says. “This troubles me and was an integral part of why I agreed to return.”

He says he directed the Secret Service ombudsman to create a method for employees to anonymously report problems and concerns to an executive review board that will ensure they can flag problems confidentially and also get a timely review of their complaint.