NFL owners unanimously approved changes to the personal conduct policy Wednesday, but Commissioner Roger Goodell will retain authority to rule on appeals.
A special counsel for investigations and conduct will oversee initial discipline, Goodell said.
"This will be a highly qualified individual with a criminal justice background hired as soon as possible for the newly created position," Goodell said. "The person will oversee our investigations and decide the discipline for violations of the policy."
The commissioner also may appoint a panel of independent experts to participate in deciding an appeal.
A more extensive list of prohibited conduct will be included in the policy, as well as specific criteria for paid leave for anyone charged with a crime of violence, including domestic violence.
The players' union has sought negotiations with the NFL on any revamping of the policy, and said Tuesday it would "reserve the right to take any and all actions" should the owners act unilaterally. The union could consider Wednesday's vote by the owners as a violation of the collective bargaining agreement reached in 2011 to end the lockout of the players.
"We expected today's vote by the NFL owners from before Thanksgiving," NFL Players Association spokesman George Atallah said on Twitter. "Our union has not seen their new policy."
That new policy will include a conduct committee made up of several team owners that will review the policy at least annually and recommend appropriate changes. That committee will seek advice from outside experts, the NFL said.
Members of the committee will be Arizona Cardinals owner Michael Bidwill as the chairman; Atlanta Falcons owner Arthur Blank; Kansas City Chiefs owner Clark Hunt; Dee Haslam, the wife of Cleveland Browns owner Jimmy Haslam; Dallas Cowboys executive vice president Charlotte Jones Anderson, chairwoman of the NFL Foundation; Chicago Bears owner George McCaskey; Houston Texans owner Robert McNair; and two former NFL players who have a stake in NFL team ownership, Warrick Dunn of the Falcons and John Stallworth of the Steelers.