The Philippines officially withdrew from the International Criminal Court (ICC) on Sunday, a year after President Rodrigo Duterte announced the country would leave the organization.

Duterte’s decision became final over the weekend when the Supreme Court of the Philippines declined to grant an injunction requested by a group of human rights activists.

Duterte had announced plans to leave the organization after the ICC announced a preliminary investigation into allegations that he and his government have committed crimes against humanity and mass murder during his so-called war on drugs.

Romel Bagares, a lawyer for the rights activists, called the decision “a terrible setback in the long fight against impunity in the country,” according the New York Times, adding that the ICC was the country’s last resort given that the government has failed to stop thousands of deaths in Duterte’s bloody drug war.

Duterte began a crackdown against the sale and use of illegal drugs shortly after taking office in 2016. Critics have accused Duterte of using the campaign, which has reportedly killed thousands of people, as cover for a politically motivated attempt to consolidate power and silence his opponents.

Just last week, the president of the Philippines publicly named 46 politicians who he says are involved in the drug trade.

Amnesty International condemned the Philippines’ ICC departure in a statement on its website. “The cynical withdrawal of the Philippines from the ICC is a futile attempt to evade international justice and to halt the ICC’s work,” the statement said.

The International Criminal Court is an Hague-based intergovernmental organization “established to investigate, prosecute and try individuals accused of committing the most serious crimes of concern to the international community as a whole.” The court focuses on crimes like genocide, crimes against humanity and war crimes.

Burundi was the first and only other member to leave the ICC in 2017, after an investigation was opened into human rights abuses in the country.

Write to Amy Gunia at amy.gunia@time.com.