Disputes over the 2023 law, backed by the powerful farm lobby, have fomented the protests by Indigenous groups that say it violates their rights to ancestral lands recognized in Brazil's 1988 constitution.
The dispute is now in the hands of Supreme Court Justice Gilmar Mendes, who a year ago set up a conciliation chamber for representatives of Indigenous groups and the farm sector to find common ground.
Indigenous umbrella group APIB, which is challenging the law in the court, has left the chamber set up by the Supreme Court, arguing that its existence was disrespectful to the constitutional rights of Brazil's native communities.
"What we have there is an attempt to despoil Indigenous rights in various ways," said Mauricio Terena, an APIB lawyer, after he left a meeting with Mendes on Tuesday.
Indigenous leaders asked Mendes to disband the chamber and allow the rest of the court's bench to rule on whether the 2023 law limiting their rights is constitutional. But this week both the speaker of the House of Representatives and the president of the Senate issued letters asking Mendes to keep the conciliation chamber open.
In a statement, the justice's office said that "the chamber will not take away any protections to Indigenous peoples," but did not clarify whether the chamber would remain open.
A senior Supreme Court source said, speaking on condition of anonymity, that many Indigenous groups not represented by the protesters have embraced the chamber's discussions, including proposals to organize and allow more economic activities on their lands.
On Thursday evening, tensions between Indigenous activists and Congress overflowed, as security forces guarding the legislative houses threw tear gas bombs when protesters approached the building.
Officials from the Lower House said in a statement that protesters were trying to break into the buildings, which activists denied.
"We were just marching," said Larissa Gomes dos Santos, from the Xakriaba people, who was among the demonstrators. "A lot of our relatives got sick," she added about the tear gas.
At another march in Brasilia this week, Indigenous demonstrators carried a replica of the statue of Justice blindfolded in front of Brazil's Supreme Court, adding an Indigenous headdress.
Protesters carried signs decrying the 2023 law and the violence against tribes that they say the legislation has fueled.
In Mato Grosso do Sul, for example, a clash between farmers and members of the Guarani Kaiowa group has left several dead in recent years.
The group, which was expelled from their land in the 1950s, has been demanding the government demarcate the land as they try to reoccupy it. But during the many decades the Guarani Kaiowa were forced to stay out, several farms were established in the area, setting the stage for violent clashes.
"The situation we are going through is massacre, murder, illegal mining and logging," said Norivaldo Mendes, a leader of the Guarani Kaiowá people who took part in the march. "We need our demarcation to guarantee our lives, to guarantee the future of our children."