During a news conference on Friday, NFL Commissioner Roger Goodell promised that the league "will get our house in order."

Goodell announced that former FBI Director Robert Mueller will lead an investigation of the way the league handled the Ray Rice case, and he said that at the end of the process the league will implement new conduct policies.

"I promise you that any shortcomings he finds will lead to swift action," Goodell said. "The same mistakes will never be repeated."

Goodell has faced intense criticism over the league's handling of off-field violent behavior from some of its players. The issue came to a very public head when a video surfaced showing Rice, a star for the Baltimore Ravens, punching his then-fiancee.

At first, the NFL handed down a two-game suspension, but after mounting pressure and a second video that actually showed the punch, the league suspended him indefinitely.

The questions surrounding Goodell have been over how much he knew about the incident and when he learned it. Goodell has said that when the league decided on the two-game suspension, it had only watched one video, which showed Rice dragging Janay Palmer out of the elevator. Goodell said that the league watched another video showing him punching her inside the elevator only when the gossip site TMZ published it.

Several reports have surfaced questioning that version of events.

Goodell acknowledged that the NFL had done wrong, and that included some of his actions.

"I got it wrong on the handling of Ray Rice," Goodell said. "I got it wrong on a number of levels. ... But now I will get it right."

Goodell promised to "do whatever is necessary to make it right."

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