A previously released video showed Rice dragging an unconscious Janay Palmer from an elevator at an Atlantic City, New Jersey, casino, but the new one was taken from inside the elevator.
The video, published on the website TMZ, showed Rice punching Palmer, who is now Rice's wife, and her falling face down on the elevator floor. She appeared to smack her head on the elevator railing before slumping to the ground.
After the video's release, the Baltimore Ravens issued a one-sentence statement, saying it had terminated his contract.
A short time later, the N.F.L. suspended Rice indefinitely.
An N.F.L. spokesman said the league had not seen the new video before having earlier suspending Rice for two games and issuing a $500,000 fine, a punishment widely seen as too lenient.
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To Steinberg, however, the N.F.L. had a heavy hand in sweeping the controversy under the rug.
"The victimization of the victim is something that the Baltimore Ravens were part of because they had her appear at a press conference and apologize and then they put her apology up onto their website," Steinberg said. "The problem here is that the commissioner had a tin ear. There's no way that two games is appropriate."
The arrival of the second video should be an embarrassment to Goodell, Steinberg said.
"There's nothing on that TMZ tape that was not already relayed to both the [Ravens] and to the commissioner," he said. "They said that Ray Rice explained in great detail and was transparent about the fact that he hit his then-fiancée, knocked her out, so that's all that Goodell needed to go ahead and issue much more than a two-game suspension."