It is generally held to be unenforceable if the insured suicided while insane.
The Statute of Frauds does not invalidate a verbal guarantee, but renders it unenforceable by action.
But other kinds of illegal contracts are not so obviously wicked as to make it clear that they are unenforceable.
Hence, an agreement to sell goods is unenforceable if not supported by consideration.
Thus, a son worked for his father on his father's farm under an unenforceable contract with his uncle.
The document was plainly one-sided and would be regarded in an English court as against public policy and unenforceable.