Restatement (Second) of Conflict of Laws § 187
Definition
A provision of the Restatement directing that the parties’ choice of a state’s law in a contract will be given effect unless the chosen state has no substantial relationship to the parties to the transaction and there is no other reasonable basis for the parties’ choice, or if application of the law of the chosen state would be contrary to a fundamental policy of another state that has a materially greater interest than the chosen state in the outcome of the particular issue.