Huh? - Spoiler Alert
How does the father's final action help to exonerate his son? I can see how he would get the murderer put away for his own death but how does that prove he also killed the girl? I don't remember the girl being shot but if it was the gun why couldn't he have just directed the shot to his foot or arm instead of to the heart?
I know his death works better for dramatic effect and it serves to wind down the movie but logically why did he have to die or want to. The guy had gotten away with murder once. For all Graham knew Sanford could have paid his people to help him dispose of the body then lie saying they saw Graham attack him then leave.
There were plenty of witnesses who had seen Graham pursuing him rather violently earlier in the day. It would have also been easy to say Graham made the call then threatened him. He pulled his gun to take control of the situation. There was a struggle and Graham was killed. If someone had a gun on you and is threatening your life it's highly unusual that you'd be able to place and calmly let someone know 'whatever happens...'. Obviously though the menacing person; the one in control of the situation and is holding the gun could make such a call.
Woman, man! That's the way it should be Tarzan. [Tarzan and his mate]