Sixteen female U.S. senators have sent a letter to commissioner Roger Goodell calling for a "real zero-tolerance policy" against domestic violence in the NFL.

The letter was sent to Goodell on Thursday. In it, the senators say they were "shocked and disgusted" by the video released Monday of former Baltimore Ravens running back Ray Rice striking his then-fiancée Janay Palmer in an Atlantic City, New Jersey, casino elevator and a subsequent report by The Associated Press that a league executive received the video from a law enforcement official in April.

Editor's Picks More on Ray Rice Case

"We are deeply concerned that the NFL's new policy, announced last month, would allow a player to commit a violent act against a woman and return after a short suspension," the letter reads. "If you violently assault a woman, you shouldn't get a second chance to play football in the NFL.

"The NFL's current policy sends a terrible message to players, fans and all Americans that even after committing a horrific act of violence, you can quickly be back on the field."

The letter ends with a call for the NFL "to institute a real zero-tolerance policy and send a strong message that the league will not tolerate violence against women by its players, who are role models for children across America."

The letter was put together by Sen. Barbara Boxer, D-Calif., and was signed by 14 Democrats and two Republicans.

President Barack Obama's press secretary released a statement earlier in the week, calling the issue of domestic violence "bigger than football."

"The president is the father of two daughters. And like any American, he believes that domestic violence is contemptible and unacceptable in a civilized society," the statement said. "Hitting a woman is not something a real man does, and that's true whether or not an act of violence happens in the public eye, or, far too often, behind closed doors. Stopping domestic violence is something that's bigger than football -- and all of us have a responsibility to put a stop to it."