The NFL players' union on Thursday appealed the league's suspension of Adrian Peterson and demanded an independent, neutral arbitrator hears the case.
In a letter to its player representatives and executive committee obtained by The Associated Press, the NFLPA called Commissioner Roger Goodell's punishment ''unprecedented, arbitrary, and unlawful.''
The union also accused Troy Vincent, the NFL's executive vice president of football operations, of telling Peterson that the games he missed on a special exempt list would count as time served toward a suspension.
League officials declined comment to the AP.
Goodell on Tuesday suspended Peterson without pay for the rest of the season and told him he will not be considered for reinstatement before April 15 for his violation of the NFL personal conduct policy. Peterson pleaded no contest Nov. 4 to misdemeanor reckless assault in Texas for injuries to his 4-year-old son with a wooden switch.
Peterson has said he intended no harm to his son, only discipline. The 2012 NFL MVP played just one game for the Minnesota Vikings this season and was paid part of his $11.75 million during the leave. He will keep the money accrued while on the exempt list. But the NFL's punishment now amounts to a 14-game ban, with six unpaid weeks. That's the equivalent of a fine of more than $4.1 million.
Goodell announced Aug. 28 tougher punishment for players involved with domestic violence. That action stemmed from a torrent of criticism for the initial leniency toward former Baltimore Ravens running back Ray Rice, who was caught on camera hitting his then-fiancee and knocking her unconscious on an elevator in an Atlantic City casino. Rice was later suspended indefinitely and recently had his appeal heard by an arbitrator.
According to the enhanced policy, first offenses of assault, battery or domestic violence bring a six-game suspension.
But the union is arguing that the new policy was enacted after the incident had already occurred and shouldn't be retroactively applied to Peterson's conduct in May 2014.
The union also claims the ''NFL is making up the process and punishment as it goes - a blatant violation of the CBA.''
AP Pro Football Writer Dave Campbell contributed to this report.
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