The best similar cultural-relativity-based deduction I've read, as introduced by Wikipedia:

A story for which [Charles James] Napier is often noted involved Hindu priests complaining to him about the prohibition of Sati by British authorities. This was the custom of burning a widow alive on the funeral pyre of her husband. As first recounted by his brother William, he replied:

"Be it so. This burning of widows is your custom; prepare the funeral pile. But my nation has also a custom. When men burn women alive we hang them, and confiscate all their property. My carpenters shall therefore erect gibbets on which to hang all concerned when the widow is consumed. Let us all act according to national customs."