Fraud. Sham. A tremendous wrong. These are choice words from Oregon’s Democratic Sens. Jeff Merkley and Ron Wyden, and Republican Rep. Greg Walden about the Huntington Treaty of 1865. This week the delegation introduced a bill to nullify the contract, which has long been considered illegal by federal judges and elected officials.

“This legislation is a monumental opportunity to reverse a villainous fraud committed long ago against the Warm Springs people,” said Warm Springs Tribal council chairman E. Austin Greene Jr. in a press release.

The fraud he’s referring to is an 1865 treaty, which amended an even earlier agreement creating the Warm Springs Reservation, but it went further — mandating that Native Americans couldn’t leave the reservation without permission, or travel out of bounds to hunt and fish.

That was not what tribal leaders had signed off on in 1855, when they ceded about 10 million acres, and agreed to move to about 578,000 acres on the Deschutes, Warm Springs and Metolius rivers. The negotiation lumped several diverse tribes together, including people who came from the deserts of present-day Eastern Oregon and people who had long relied on fishing in the Columbia River Gorge.

Federal judges over the last 50 years have maintained the off-reservation hunting and fishing restrictions in the Treaty of 1865 are not enforceable, and lawmakers have taken up the issue without success since at least the 1990s.

Earlier this year Oregon Gov. Kate Brown visited the Warm Springs Tribal Council to hand-deliver a letter stating the policy of the state of Oregon is that “the fraudulent Huntington Treaty… is to be regarded as a nullity with no effect whatsoever.”

This week Brown urged Congress to act swiftly on the proposed bill, which is also backed by Oregon Attorney General Ellen Rosenblum.