Rice was originally handed a two-game suspension in July under the NFL's personal conduct policy after he was charged with assault following a Feb. 15 altercation with his then-fiancee in a casino elevator.
The Baltimore running back had already served the first game of that suspension when, on Sept. 8, a video surfaced showing Rice punching Janay Palmer, now his wife, in that elevator.
Within hours, the Ravens released Rice and NFL Commissioner Roger Goodell extended the suspension to indefinite based on the "new evidence."
Goodell and the Ravens say they never saw the video before Sept. 8.
"This action taken by our union is to protect the due process rights of all NFL players," the NFL Players Association said in a statement. "The NFLPA appeal is based on supporting facts that reveal a lack of a fair and impartial process, including the role of the office of the commissioner of the NFL. We have asked that a neutral and jointly selected arbitrator hear this case as the commissioner and his staff will be essential witnesses in the proceeding and thus cannot serve as impartial arbitrators."
The NFLPA said that the collective bargaining agreement requires a hearing date be set within 10 days of the appeal notice. It also said the hearing will require a neutral arbitrator to determine what information was available to the NFL and when it was available.
The union, which had until 11:59 p.m. Tuesday to file the appeal, added that under governing labour law, an employee can't be punished twice for the same action when all of the relevant facts were available to the employer at the time of the first punishment.
"The erratic and illogical system of ad hoc punishments is a paltry substitute for the leadership the NFL desperately needs right now," National Organization for Women President Terry O'Neill said in a statement. "Roger Goodell must resign, and his successor must be fully committed to real and lasting change."
Rice can apply for reinstatement when he convinces Goodell that he is "addressing this issue." Rice has been accepted into a diversion program, which upon completion could lead to the assault charge being dropped.
The NFL said that Goodell never intended to personally hear Rice's appeal.
The NFL has come under heavy scrutiny for its handling of the Rice situation — and other domestic violence cases — as the league tries to attract female fans to the game. It is an effort that has been scarred by the original two-game suspension, a punishment many women's organizations deemed too light.
Goodell, in a letter sent to all 32 NFL owners in August, acknowledged that he "didn't get it right."
He then announced a new policy, stating that first-time domestic violence offenders would face a six-game suspension, and repeat offenders would be suspended indefinitely.
The policy didn't apply to Rice, who had already received his penalty.
There is apparently no precedent for the indefinite suspension Rice received after the video surfaced.
With all questions about who knew what and when — The Associated Press has reported the video was sent to NFL offices in April — the league has hired former FBI director Robert Mueller to look into how the NFL sought and handled evidence in the domestic violence case.
Soon after receiving the original suspension, Rice called his actions in the elevator "inexcusable" and apologized publicly to Janay, his mother, his teammates and the Ravens organization.
He also addressed the length of the suspension, which came with a fine of three paychecks totalling more than $500,000.
"I never planned to appeal any kind of punishment," Rice said on July 31. "So whether it was two games, four games, six games, eight games, I was going to own my actions and be a man about it and take whatever was given to me."
At that time, he spoke about the damage his reputation received.
"In some people's eyes, Ray can do no wrong. That's something I take pride in," he said. "I know a lot of people out there have lost respect, maybe not like me anymore. But that's my fault. I have to own that. That's my battle each day."
It is a battle he has waged recently out of the public eye. Although he attended a football game at his former high school with his wife last weekend, he has not spoken to the media since his release from the Ravens.
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