In Sun Insurance Co. v. Kountz Line, the Supreme Court of the United States was asked to determine whether a contract of marine insurance was valid. The contract was between the Sun Insurance Company and the Kountz Line, a steamship company. The contract provided that the Sun Insurance Company would insure the Kountz Line against any losses incurred while transporting goods from one port to another. The Kountz Line was transporting goods from New York to San Francisco when the goods were lost due to a storm. The Sun Insurance Company refused to pay the claim, arguing that the contract was invalid because it had not been approved by the New York Insurance Department. The Kountz Line argued that the contract was valid because it had been approved by the California Insurance Department. The Supreme Court held that the contract was valid and that the Sun Insurance Company was liable for the losses incurred by the Kountz Line. The Court reasoned that the contract was valid because it had been approved by the California Insurance Department, and that the New York Insurance Department had no authority to invalidate the contract. The Court also held that the Sun Insurance Company was liable for the losses incurred by the Kountz Line because the contract was valid and the losses were caused by a storm, which was a risk covered by the contract.

Justice Field delivered the dissenting opinion in Sun Insurance Co. v. Kountz Line, arguing that the majority's decision was contrary to established precedent and would lead to confusion among lower courts. He argued that a contract of insurance is not an ordinary commercial transaction but rather one which involves public policy considerations, such as protecting those who are insured from financial loss due to unforeseen events or circumstances beyond their control. Thus, he reasoned, it should be subject to special rules and regulations designed for its protection; these rules must be strictly construed against insurers so as not to prejudice the rights of individuals seeking coverage under them. Furthermore, Justice Field noted that prior decisions had held that when an insurer has accepted premiums without reserving any right or condition inconsistent with its terms then it cannot later rely on conditions contained within those policies if they were unknown at the time of acceptance - even if they are subsequently discovered by either party after issuance of the policy itself. Therefore he concluded that since there was no evidence presented showing any reservation made by Sun Insurance Company at the time it issued Kountz Line's policy then it could not now rely upon a provision found therein which purported to limit liability for losses occurring during certain periods specified therein; thus reversing judgment entered below in favor of Kountz Line would be unjustified and unwarranted according