that part about washing off the roof with a hose made me remember about an unsolved murder here in Erie, PA
a police officer was shot and killed, with his own gun, it was originally ruled a suicide, they claim he shot himself in the chest.
this was in the winter, the first officers to arrive on the scene used a fire hose to wash all the snow away, they claimed they were looking for his gun, they also washed away any evidence too.
the gun was not at the scene but recovered blocks away along the railroad tracks.
still unsolved.