NFL Commissioner Roger Goodell, who was widely criticized for mishandling the Ray Rice investigation and being slow to address domestic violence, said Friday that it has been a year of "humility and learning" for the league and for him.
He said that he could not see a circumstance under which he would resign.
"It's been a tough year on me personally," he said. "We obviously as an organization have gone through adversity, but more importantly it's been adversity for me. We take that seriously. It's an opportunity to get better."
He added: "We've all done a lot of soul-searching, starting with yours truly, and we have taken action."
Goodell first suspended Rice for two games after video emerged of Rice dragging the unconscious body of his fiancée out of a casino elevator. He leveled an indefinite suspension against Rice, a former running back for the Baltimore Ravens, when a second video emerged showing a knockout punch. An arbitrator found that Goodell and abused his direction, and she reinstated Rice.
Goodell spoke of visiting a domestic-violence shelter and seeing fear in the victims.
"That is compelling, and it will make you understand this issue much more deeply," he said. "This commissioner understands it a lot better today than he did before."
On the controversy known as Deflate-Gate, the commissioner said that the NFL is conducting a "thorough and objective" investigation into whether the New England Patriots deliberately let air out of footballs in the AFC title game.
But he stressed that the league had not reached a judgment on whether anyone did anything wrong.
"We take seriously anything that potentially impacts the integrity of the game," Goodell said at a press conference in Glendale, Arizona, two days before Super Bowl XLIX, between the Patriots and the Seattle Seahawks.
He pledged to make the league's report public.
Asked about an assertion by Patriots owner Robert Kraft that the league owes the team an apology when it turns out nobody broke the rules, Goodell said: "This is my job. This is my responsibility, to protect the integrity of the game. I represent 32 teams. All of us want to make sure that the rules are being followed."
Addressing the league's concern about concussions and brain damage, he said that the league plans to hire a chief medical officer. He said that concussions were down 25 percent from last season, and that hits to defenseless players were down 68 percent.