The NFL called in a former FBI director to examine how it pursued and handled evidence in the Ray Rice domestic violence case as pressure increased for the league to be more transparent about its original investigation.

The move late Wednesday came hours after The Associated Press reported that a law enforcement officer said he sent an NFL executive a video in April that showed Rice striking his then-fiancee at a casino. Goodell has maintained that no one in the NFL saw the video until it was released by TMZ Sports Monday.

Women’s organizations, members of Congress and players have called for more detail about the NFL’s handling of the Rice case. The criticism intensified after the law enforcement official’s account.

Goodell turned to Robert S. Mueller III, who was the director of the FBI for a 12-year term, to lead the inquiry. The probe will be overseen by owners John Mara of the New York Giants and Art Rooney of the Pittsburgh Steelers, two of Goodell’s strongest supporters. Both are members of key NFL committees and have closely advised Goodell throughout his tenure.

The law enforcement official who described sending the video to the NFL spoke on condition of anonymity because an investigation is ongoing. He said he sent the tape five months ago, and played a 12-second voicemail from an NFL office number on April 9 confirming the video arrived. A female voice expresses thanks and says: “You’re right. It’s terrible.”

The official says he had no further communication with any NFL employee and can’t confirm anyone watched the video. The person said he was unauthorized to release the video but shared it unsolicited, because he wanted the NFL to have it before deciding on Rice’s punishment.

The NFL has said it asked for the video from law enforcement, but was denied.