Tagliabue, NFL commissioner from 1989 through 2006, was named by current Commissioner Roger Goodell to conduct an appeal hearing for four players who have been suspended by the league.
The players were allegedly part of an attempt to injure members of opposing teams in exchange for cash. The various punishments and fines imposed by the league include the suspension of New Orleans Coach Sean Payton for the entire season.
The hearing for players Jonathan Vilma, Will Smith, Anthony Hargrove and Scott Fujita has been scheduled for next Tuesday with Tagliabue set to hear arguments and then make a ruling as to whether the suspensions will be reduced, eliminated or left unchanged.
The suspensions range from an entire year for Vilma to one game for Fujita.
"To comply with the court-ordered schedule, we will be making a motion under the collective bargaining agreement to recuse Paul Tagliabue today," the union said in a statement.
The motion was to be filed in the U.S. district court in New Orleans. The NFL will have until Friday at 5 p.m. ET to answer the motion and the union will then have until next Monday to respond.