Sacrificing yourself for another is not suicide! Jesus himself says no greater love has he than he who lays down his life for another! He wasn’t suicidal, he was acting out of love!
This is a good way to put this into proper perspective.
This fellow was not suicidal. Suicide is the action of killing oneself intentionally. The fathers own death was somewhere on the back burner, if at all even thought of. He was a hero acting out of love.
It may be a cops duty to stop a suicide, but this was clearly not the case.
For someone else's life, it is not suicide.
For someone else's corpse, it is.
He was not trying to kill himself - he was not thinking of himself.
Objectively, however, the cop saw that the net effect of his actions were suicide.