A central focus of the review is a 2007 background check of Mr. Alexis conducted by US Investigations Services LLC, a Falls Church, Va., company facing a criminal investigation over allegations that it rushed cases through the clearance process without proper review.

Last week, the Office of Personnel Management, the agency in charge of overseeing most federal background security checks, said USIS had conducted a complete investigation of Mr. Alexis, including information on the 2004 arrest.

On Monday, the agency said Mr. Alexis had turned in an incomplete security background form in 2007 that omitted information about the arrest as well as financial problems in his past. After uncovering the problems in the normal course of the examination, investigators asked the Seattle Police Department for information on Mr. Alexis. But the department refused, according to the OPM…

“Had the Seattle Police Department permitted OPM to obtain the law-enforcement records, it is possible that additional information may have been obtained,” according to an agency official. “However, OPM cannot compel police departments to cooperate.”