Klein v. Insurance Company was a United States Supreme Court case that addressed the issue of whether a contract of insurance was valid when the insured had not paid the premium. The plaintiff, Klein, had purchased a policy of insurance from the defendant, an insurance company, but had failed to pay the premium. The insurance company refused to pay the claim, arguing that the policy was void due to nonpayment of the premium. The Supreme Court held that the policy was valid and enforceable, despite the nonpayment of the premium. The Court reasoned that the policy was a contract of indemnity, and that the parties had agreed to the terms of the policy. The Court further held that the insurance company was obligated to pay the claim, as the policy was valid and enforceable. The Court's decision in Klein v. Insurance Company established that a contract of insurance is valid and enforceable, even if the insured has not paid the premium. This decision has been cited in numerous subsequent cases, and has been used to support the validity of insurance contracts.

Justice Field delivered the dissenting opinion in Klein v. Insurance Company, arguing that the majority's decision was contrary to established precedent and would lead to a dangerous expansion of federal power. He argued that Congress had no authority under Article I of the Constitution to pass legislation regulating insurance companies as it did in this case, since such regulation is not an enumerated power granted by the Constitution. Furthermore, he noted that if Congress were allowed to regulate insurance companies through its Commerce Clause powers then it could effectively control any business activity within state borders - something which was never intended by our Founding Fathers when they drafted the Constitution. Finally, Justice Field warned against allowing Congress too much leeway with respect to its regulatory powers because doing so would ultimately undermine states' rights and create an imbalance between federal and state governments.