Indigenous communities across Brazil have suffered a wave of violence in recent weeks as the country reconsiders a controversial law that makes it harder to claim ancestral territory.

The Supreme Court is studying a law that only recognizes territorial rights for Indigenous people if they occupied the land after a certain date. But critics say it delegitimizes many land claims and fuels conflicts with farmers, ranchers and private developers who see an opportunity to expand.

“The right to traditionally occupied territory is an original right secured by the 1988 federal constitution and cannot be negotiated,” Kleber Karipuna, executive director of the Articulation of Indigenous Peoples of Brazil (APIB), said in a statement. “We need to guarantee that Indigenous lands are demarcated and protected in order to combat climate change.”

The debate has focused on a provision in the law that only recognizes Indigenous land if it was occupied as of October 5, 1988, when the country’s current constitution was ratified. But many Indigenous communities were forcibly displaced from their land before that date and didn’t always have the legal means to appeal, according to Funai, Brazil’s Indigenous affairs agency.

The law leaves approximately 14% of Brazilian territory vulnerable to development, according to APIB estimates. Currently, there are more than 500 requests for regularization of Indigenous lands.

Across the globe, Indigenous people are believed to protect 80% of all biodiversity, making the law an environmental concern in addition to a human rights one.

Last month, Ava Guaraní denounced attacks by armed farmers in Paraná state, which they say came in response to attempts to formally reclaim ancestral land. At the same time, dozens of armed men have invaded Indigenous Anacé territory in Ceará state with heavy machinery and livestock, destroying the tents that families had been staying in since returning to the land in 2023. Multiple attacks have also been reported in Rio Grande do Sul, Bahia and Mato Grosso do Sul.

“As this goes on longer, I think the farmers become more emboldened,” said August Shipman, a researcher at the University of Connecticut who witnessed threats and violence firsthand in Guarani-Kaiowá reoccupation zones in Mato Grosso do Sul.

At least 208 Indigenous people were murdered last year, a 15.5% increase since 2022 and one of the highest murder rates in nearly a decade, according to the Missionary Indigenous Council, an Indigenous rights advocacy group in Brazil.

Before being enshrined as law, the provision (known as marco temporal in Portuguese, or “time frame”) was struck down by the Supreme Court last September. However, the conservative-led Brazilian Congress approved it in a new bill and then upheld it after President Lula da Silva tried to veto parts of it. The bill is heavily backed by agribusiness organizations, which claim that all land in Brazil was once Indigenous and every land property could become a protected territory eventually — which is false by Funai rules. Hence, a time limit is needed to protect landowners, proponents of the law say.

Since Congress turned the concept into law, Funai and other Indigenous advocacy groups have filed lawsuits against the bill, questioning its constitutionality.

In addition to arguing that Indigenous people have a right to the land even if they didn’t occupy it before 1988, Funai claims that the law creates “excessive requirements” that make demarcating land unnecessarily difficult and time-consuming. It also weakens their right to free, prior and informed consent, which requires that communities be consulted before development projects can be carried out.

“Such provisions not only consolidate the violation of the rights of Indigenous peoples, but also hinder the implementation of Indigenous policy,” Funai said in a statement.

In April, a court suspended all legal proceedings related to the time frame debate until better guidelines and interpretations could be established for the law. Last week, the Supreme Court held its first “conciliation meeting” for that process. It’s expected to last until December under heavy criticism of Indigenous organizations, which say the Supreme Court is forcing them to negotiate a constitutional right guaranteed by the same Supreme Court in September.

In response to the violence against Guarani-Kaiowá communities, the Ministry of Justice and Public Security said it will increase the number of personnel, vehicles and equipment in Mato Grosso do Sul. It will also create a situation room to better respond to security demands.

But Funai and other advocacy groups maintain that a long-term solution would involve declaring the timeframe law unconstitutional for good.

“Society needs to be made aware of the history of violations of the rights of Indigenous peoples,” said Funai president Joenia Wapichana. “How many peoples have been decimated by land disputes or expelled from the areas they traditionally occupied without being able to adequately defend themselves in legal actions that have taken away their right to territorial policy?”