The acting governor of the Brazilian state of Rio de Janeiro should seek passage of a bill for independent forensic services in the state and take additional measures to strengthen forensic analysis, Human Rights Watch said today in a letter to the acting governor, Ricardo Couto.
Rio de Janeiro remains one of six Brazilian states, together with the federal district, that still have official forensic units fully subordinate to civil police, who investigate crimes, including killings by the police. About 77 percent of homicides remain unsolved in Rio, one of the highest rates in Brazil. In addition, Human Rights Watch has identified serious shortcomings in investigations led by civil police into killings by police.
“Ensuring high-quality, independent forensic services is key to improving criminal investigations and accountability in Rio de Janeiro,” said Andrea Carvalho, Brazil researcher at Human Rights Watch. “Rio’s acting governor should seek to grant forensic experts the support and independence they need to be effective.”
Several crime scene analysis forensic experts told Human Rights Watch of veiled pressure by police to influence their work, particularly in cases of police killings.
The administration has already taken important steps to strengthen the forensic services that do not require legislative approval. On May 5, 2026, a news outlet reported that the acting governor had decided to give “full autonomy” to forensic services.
On May 21, the secretary of civil police, who reports to the governor, established that only staff reporting to the forensic department can conduct forensic analysis. The secretary also created specialized forensic units to work on homicide cases that will report to the state’s forensic department instead of being under the direct supervision of civil police officers, though the forensic department remains subordinated to the civil police.
Rio is the only Brazilian state in which a police officer leads the forensic services, instead of a forensic expert. The chief of civil police controls the budget for forensic services and may prioritize resources for police, such as vehicles or weapons, rather than the purchase or maintenance of laboratory equipment needed for forensic work, Human Rights Watch said.
Acting governor Couto should introduce a bill that guarantees forensic services are fully independent from the civil police, Human Rights Watch said. The bill should ensure that forensic services are led by forensic experts, have their own budget and their own office of internal affairs, and that experts undergo training that is separate from civil police.
In the meantime, the governor should already appoint a forensic expert as head of forensic services to ensure that the leadership has the technical expertise to ensure high-quality forensic analysis and to bring the perspective of forensic experts to high-level decision-making processes within the civil police.
The governor should also hold civil service exams to hire additional forensic experts and medical examiners, Human Rights Watch said. In April 2025, the Secretariat of the Civil Police told Human Rights Watch that 57 percent of the forensic doctor positions provided by state law were vacant, as well as 26 percent of the forensic expert positions.
Both the Inter-American Court of Human Rights and Brazil’s Supreme Court have ordered thorough and independent investigations into police abuse cases in Rio de Janeiro. Having independent forensic analysis is a crucial part of such investigations, Human Rights Watch said.
“Forensic services should be independent to ensure they are based solely on science, to prevent conflict of interest or bias, to preserve the credibility of the findings in court, and to avoid judicial errors,” Carvalho said. “Independence is particularly important when forensic experts review the circumstances of a police killing.
