OK, if his murderer failed his psych eval, was hired anyway AND every officer he worked with knew he was a loose canon, should everyone in that supply chain, the hiring manager, the police academy instructors, all the chain of command in the department, internal affairs, all his colleagues, etc. be held to the same standard?
Do you know if he failed a psych evaluation? You keep positing that hypothetical and then answering your own questions as if he did indeed fail the psych evaluation.