(Saul Loeb/AFP-Getty – Police investigate a shooting at the Navy Yard on Sept. 16.)

The House Oversight and Government Reform Committee has scheduled a hearing for Tuesday to examine the federal government’s security-clearance process, focusing on Washington Navy Yard shooter Aaron Alexis and how to improve background checks.

The deceased gunman in the September rampage obtained a “secret level security clearance” despite a history of questionable behavior, according to a hearing notice.

A Washington Post profile said Alexis was “discharged from the Navy Reserve, arrested after firing a bullet through his upstairs neighbor’s floor and then asked to leave his Fort Worth apartment.” Authorities have said he also showed signs of mental illness.

MORE: Navy Yard shooter driven by delusions

The security-services firm USIS screened both Alexis and National Security Agency leaker Edward Snowden, and federal authorities filed a lawsuit last month saying the company submitted 660,000 background checks without properly reviewing their investigations.

The Office of Personnel Management’s Federal Investigative Services division oversees U.S. government security clearances, but contractors, especially USIS, do much of the work. The firm’s chief executive officer, Sterling Phillips, is scheduled to testify at the hearing on Tuesday, along with OPM Director Katherine Archuleta, who was confirmed to her position in October, and other witnesses.

USIS said in a statement last month that the alleged conduct in the federal lawsuit runs counter to its values and commitment to service, adding that they “relate to a small group of individuals over a specific time period and are inconsistent with the strong service record we have earned since inception in 1996.”

Last week, Archuleta announced that the U.S. government will no longer use contractors to review the quality of their own work, instead relying on federal employees to do the job, starting on Feb. 24.

The House Oversight hearing takes place at 10 a.m. and can be streamed live through the committee’s Web site.

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