Powell killed himself and his two sons in February. When the caseworker, Elizabeth Griffin-Hall, brought the boys to his house for a supervised visit he grabbed them, barring her from the house and set off an explosive fire.
The Child Fatality Review released Wednesday was a 12-page report done by an independent group that includes a judge, police officer, lawyers and two state senators as well as social service workers, the Seattle Times reported. The panel concluded child welfare officials should have discussed the case with police before allowing Powell to have home visits with the boys.
After Powell's wife, Susan Cox Powell, vanished in Utah in December 2009, he moved back to the Tacoma, Wash., area, where both their families live. He told police in Utah he took the boys on a short winter camping trip and returned to find his wife gone. Police suspect he killed her but have been unable to find her body.
Powell lost custody of his children after his father was charged with secretly photographing women and teenage girls.
The report generally praised the conduct of Griffin-Hall and others involved in the case and said that it is possible nothing they could have done would have made a difference.