Washington DC - Just ahead of Indigenous Peoples' Day, dozens of Democratic and Republican US lawmakers joined forces to call for the release of imprisoned freedom fighter Leonard Peltier.

Led by Arizona Representative Raúl Grijalva, 33 members of Congress signed on to a bipartisan letter, dated October 6, urging President Joe Biden to grant clemency or compassionate release to American Indian Movement icon Leonard Peltier, who has spent nearly five decades behind bars on dubious charges.

"As Members of Congress, we sign this letter with a deep commitment to the crucial role we play in upholding justice for all Americans – and to also hold our government accountable when we see a case of injustice, as demonstrated by the long incarceration of Leonard Peltier," the signatories wrote.

The letter points to the overwhelming calls for Peltier's liberation from a variety of sources, from esteemed civil rights leaders, to members of the case's prosecution team, to the United Nations Working Group on Arbitrary Detention.

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"We stand with the Tribal Nations of the United States, Indigenous voices worldwide, and leading voices on human rights and criminal justice around the globe in support of Mr. Peltier's release," the lawmakers affirm.

A member of the Turtle Mountain Band of Chippewa, Peltier has dedicated his life to the struggle for Indigenous rights and the fight against racism and police brutality.

Peltier was taken into US custody after he was convicted of killing two FBI agents in a shootout on the Pine Ridge Indian Reservation in South Dakota in June 1975, following the infamous 1973 Wounded Knee occupation. He was sentenced to two terms of life imprisonment and is currently incarcerated in a maximum-security facility in Coleman, Florida.

Many of Peltier's supporters have pointed toward irregularities in the 1977 murder trial, noting that the FBI had coerced witnesses and excluded and falsified evidence. Even the top prosecutor in the case, former US Attorney James Reynolds, has called for Peltier's release.

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The congressional letter once again requesting clemency came just weeks after Indigenous rights advocates rallied at the White House, and around the world, on Peltier's 79th birthday last month.

"I may leave this place in a box. That is a cold truth. But I have put my heart and soul into making our world a better place and there is a lot of work left to do – I would like to get out and do it with you," the political prisoner said in a message to supporters at the time.

"I long to turn my face to the sky," he added. "In this cage, I am denied that simple pleasure. I am in prison, but in my mind, I remain as I was born: a free Native spirit."