(Reuters) - An attempt by Adrian Peterson to get back on the field reaches an important stage on Tuesday when the suspended Minnesota Vikings running back squares off against the NFL in a hearing over his punishment for child abuse.
Peterson was suspended two weeks ago by the National Football League without pay for at least the remainder of the 2014 season for using a tree branch to discipline his son.
But Peterson contends, in part, that the league's strengthened sanctions for domestic abuse announced in late August should not have any effect on his offense, which occurred in May.
The hearing will be heard by Harold Henderson, the NFL's former executive vice president of labor relations who has heard 87 appeals since 2008 involving personal conduct and drug issues.
NFL Commissioner Roger Goodell has been under fire over what is widely seen as the league's soft approach to dealing with domestic violence issues.
Goodell slapped Ray Rice with a two-game ban for knocking out his wife but hiked the sanction to an indefinite suspension after video emerged of the punch.
In what may give a boost to Peterson's chances, an independent arbitrator ruled last Friday that Rice was sanctioned twice by Goodell for the same crime and said the former Baltimore Ravens running back can sign with any team.
Peterson, the 2012 NFL MVP, has played in only one game this year after being charged with child abuse and being placed on the commissioner's exempt list, which takes the player off the field but allows him to keep his $11.75 salary.
He was arrested in September on a felony child abuse charge for disciplining his 4-year-old son by repeatedly striking him with a thin tree branch called a switch.
Peterson, 29, pleaded no contest in Conroe, Texas, to a misdemeanor assault charge and was ordered to pay a $4,000 fine and perform community service.
The union said Peterson was told that after his legal case was resolved he would be allowed to play again. Goodell disputed that, saying Peterson was always subject to NFL discipline regardless of the outcome of his legal case.
Goodell said Peterson will not be considered for reinstatement before April 15 for violating the NFL Personal Conduct Policy.
There was no timetable for when Henderson will reach a decision.
(Reporting by Steve Ginsburg in Washington)