The justifiability of this shooting will be determined in the courtroom. However, it’s fairly safe to say that not reporting a shooting/killing to the POlice and subsequently tampering with evidence, i.e., throwing the spent shell casings in the dumpster and concealing the revolver, is unlikely to help your case.
Win, Lose, or Draw; the cost of this killing will be high, both psychologically and financially.
Also, the optics of two shots to the back of the head are not good.
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This might also be tough to explain;
A University of Wisconsin pathologist found during an autopsy the next day that two projectiles had entered the back of Lytle’s head near his neck and proved fatal.