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.…