Post Mortem Skin Analysis

If a person shoots someone with an obvious intent to incriminate the victim. Can the offender immediately following the death of the victim then scratch himself with the victims fingernails to show a sign of struggle and get away with it?


To my understanding there is an analysis that can be tested to determine the person was was already deceased when the skin by scratched by the victims fingernails. The theory is because skin requires 7lbs of force to penetrate. It would force the fingernails to either crack under the fingernail or split the skin like a paper cut that would usually bleed.

Can the individual in this scenario escape forensic science? I believe that the offender cannot but this is an inquiry.