Sen. Maria Cantwell (D-Wash.) announced Tuesday that she will introduce legislation to eliminate the NFL’s tax-exempt status because of its refusal to address the name of the Washington Redskins.

Flanked by several tribal chiefs, Cantwell, who is the former chair of the Senate Indian Affairs Committee, condemned the team’s name as a slur against Native Americans.

“The NFL needs to join the rest of Americans in the 21st century,” she said. “It is about right and wrong.”

Cantwell made her remarks at a press conference called by a coalition of Native American and social justice groups leading the campaign against the Redskins’ name.

The group, Change the Mascot, which includes the National Congress of American Indians and the Oneida Indian Nation, is calling on the owners of the 31 other NFL teams to force fellow owner Dan Snyder to change the team’s moniker.

Where notable people stand on the Redskins’ name

Cantwell and Rep. Tom Cole (R-Okla.) sent a letter in February to NFL Commissioner Roger Goodell warning that the league was endangering its tax-exempt status by refusing to take action on the team’s name. But previous efforts to end the tax break — the hugely profitable and popular NFL is considered a non-profit organization — have gone nowhere. A tax reform package sponsored by House Ways and Means Committee Chairman Dave Camp (R- Mich.) includes a repeal of tax-exempt status for professional sports leagues. It is languishing in committee.

Cantwell’s push comes at a time when the league and Goodell are under intense fire for the way domestic violence cases against players Ray Rice and Greg Hardy were handled, along with child abuse charges against Adrian Peterson. And last week, the league acknowledged in federal court documents that it expects nearly a third of retired players to develop Alzheimer’s disease, dementia or other serious health problems from concussions suffered on the field.

But the NFL, which generates about $10 billion in annual revenue, remains a powerful presence in political Washington. It spends millions on lobbyists and its officials and political action committee donated more than $1.4 million to lawmakers during the past two election cycles, according to data from the Center for Responsive Politics.

Snyder has been insistent that he will not change the team’s name, arguing that the word “Redskins” is not a slur and that it’s meant to honor Native Americans. Goodell has voiced support for Snyder’s efforts to help Native Americans through a new foundation and noted that public polls show overwhelming support for the team’s name.

The Change the Mascot group is sending the NFL owners a letter arguing that league bylaws enable them to punish any owner or part-owner who is “guilty of conduct detrimental” to the sport.

“Clearly, Washington team owner Dan Snyder’s continued promotion of this racial slur represents such conduct,” reads the letter, signed by Ray Halbritter, the representative of the Oneida Indian Nation, and Brian Cladoosby, the president of NCAI. “Put simply, Mr. Snyder is jeopardizing the welfare of the league by promoting an epithet against people of color.”

The letter is one of a series of new initiatives announced Tuesday at the press conference featuring Cantwell, who represents the reigning Super Bowl champion Seattle Seahawks; Rep. Betty McCollum (D-Minn.); D.C. Del. Eleanor Holmes Norton (D), and senior officials from the NAACP. In June, McCollum wrote one NFL owner herself — Zygi Wilf, the owner of the Minnesota Vikings. She argued that since all the NFL owners split sales of team merchandise, he is obligated to condemn Washington’s team name and pressure Snyder to change it. Wilf did not respond, she said.

Ray Halbritter, Oneida Indian Nation representative, speaks during a press conference at the Dirksen Senate Building on Tuesday. (Nikki Kahn/The Washington Post)

In its letter, the Change the Mascot campaign argues that because the NFL enjoys tax-exempt status and antitrust exemptions, team owners have a duty to ensure that “taxpayer resources are no longer being expended to promote this slur.”

“The NFL’s continued promotion of this racial slur is not just about one particular team. The league is promoting this racial slur with the resources of every team, including yours, which makes it a league-wide crisis,” the letter reads.

In May, 50 members of the U.S. Senate, all Democrats, wrote letters to Goodell asking him to advocate for the Redskins to change the team’s name.

None of the public pressure has had an impact on Snyder, including a recent decision by the U.S. Patent and Trademark Office to strip the team of its Redskins trademarks because it found the name offensive to a sizable proportion of Native Americans. Snyder currently is appealing that ruling in federal court.