At the end of a Catholic Mass, the priest bids the congregation farewell by telling parishoners "go in peace, to love and serve the Lord" to which those in the pews respond "thanks be to God."*
Now, imagine that a member of said congregation in attendance at Mass the previous Sunday was accused of committing a brutal murder the following Thursday. Under police questioning, the lead investigator tells our chruchgoer, "you can't account for your whereabouts at the time of the murder, your DNA was found under the victim's fingernails, and a bloody hammer was found in your car. How do you explain all this?"
Our devoutly Catholic murderer explains "I couldn't possibly have done it. I was in church last Sunday, and the priest told us all sorts of things about loving our neighbours and told us to go in peace. No one could disobey such Godly commands!"
