An imprisoned double cop killer sentenced to death 40 years ago has failed again in a bid to overturn a parole board decision that denied him freedom. Richard Ambrose, 66, is confined to a medium-security prison in British Columbia but he desperately wants out. He is “aggressive,” “hostile,” “confrontational,” has threatened his lawyers and, recently, a psychologist concluded he is a “high risk” to reoffend, according to documents acquired from the Parole Board of Canada. In 1974, Ambrose (inset) and career criminal James Hutchison shot two Moncton, N.B. city police officers in the head and buried the bodies in shallow graves. Quickly caught and convicted, Ambrose and Hutchison were condemned to hang but the sentences were commuted to life in prison after the abolition of the death penalty in Canada. Ambrose has been rebuffed twice in the past three years in complaints to a parole appeal body.