Connecticut Mutual Life Insurance Company v. Spratley was a United States Supreme Court case that addressed the issue of whether a life insurance policy could be assigned to a third party without the consent of the insurer. The Court held that the policy could not be assigned without the insurer's consent, as the policy was a personal contract between the insurer and the insured. The case arose when the insured, Spratley, attempted to assign his life insurance policy to a third party without the consent of the insurer. The insurer, Connecticut Mutual Life Insurance Company, argued that the policy was a personal contract between the insurer and the insured, and that the policy could not be assigned without the insurer's consent. The Court agreed with the insurer, holding that the policy was a personal contract and that the assignment was invalid without the insurer's consent. The Court's decision in this case established that life insurance policies are personal contracts between the insurer and the insured, and that the policy cannot be assigned to a third party without the insurer's consent. This decision has been cited in numerous subsequent cases, and has become an important precedent in the area of life insurance law.

In Connecticut Mutual Life Insurance Company v. Spratley, the Supreme Court was tasked with determining whether a life insurance policy issued to an individual in Virginia could be enforced by his widow and children after he had moved to North Carolina. The majority opinion held that the policy was valid and enforceable despite the fact that it had been issued in another state because there were no laws prohibiting such contracts from being made between citizens of different states. Justice Field dissented on this issue, arguing that since both parties resided in different states at the time of enforcement, it would be unconstitutional for one party (the insurer) to have rights under a contract which did not exist when it was formed or executed. He argued further that allowing such contracts would violate public policy as well as interfere with interstate commerce due to its potential for fraud and abuse if insurers could take advantage of individuals who may not understand their rights under these types of policies.