In the 1941 case of MacGregor, Executor v. State Mutual Life Assurance Co., the United States Supreme Court was tasked with determining whether a life insurance policy could be considered valid if the insured committed suicide within two years of obtaining it. The insurer had denied payment on grounds that their policy contained a clause excluding coverage for death by suicide within two years from its date. However, Mr. MacGregor argued that this exclusion violated Massachusetts law which prohibited such clauses in life insurance policies issued to residents of the state. The court ruled in favor of State Mutual Life Assurance Co., stating that while Massachusetts law did indeed prohibit certain types of exclusions in life insurance policies, it did not apply to contracts made outside its jurisdiction and thus could not govern an agreement made between parties in another state (in this case New York). Therefore, since both parties were based out-of-state when they entered into contract and because there was no evidence suggesting intent to evade Massachusetts laws or defraud anyone involved, the suicide exclusion clause remained enforceable and consequently invalidated any claim on benefits under these circumstances.

In the dissenting opinion for MacGregor v. State Mutual Life Assurance Co., Justice Frankfurter argued that the majority's decision to uphold a lower court ruling, which found in favor of an insurance company denying payment on a policy due to suicide, was incorrect. He believed that it was not clear whether the insured had committed suicide or died accidentally and thus, there should be no presumption of intent without substantial evidence. The burden of proof should lie with the insurer rather than shifting it onto beneficiaries who are often unable to provide definitive evidence regarding circumstances surrounding death. Furthermore, he pointed out inconsistencies in how courts interpret ambiguous clauses within insurance policies - sometimes they're interpreted against insurers while other times they're used as grounds for denial of claims by these companies.