Duncan M'Arthur, plaintiff in error, brought a case against Wesley S. Porter, defendant in error. The dispute arose from an agreement between the two parties for the sale of goods and services. According to the contract, M’Arthur was to provide Porter with certain items such as wheat and flour at a fixed price over a period of time. However, when it came time for payment on these goods and services provided by M’Arthur, Porter refused to pay him what he was owed under their agreement. In response to this breach of contract by Porter, M’Arthur sued him for damages incurred due to his refusal or inability to make payments according to their original arrangement. Ultimately after much deliberation on both sides of the argument presented before Supreme Court justices at trial level proceedings; justice prevailed as they ruled in favor of Duncan Mcarthur awarding him damages that were deemed appropriate based upon evidence presented during court proceedings related directly back too contractual obligations agreed upon initially between both parties involved prior too any legal action being taken place within court system itself .

In the case of Duncan M'Arthur v. Wesley S. Porter, the Supreme Court was asked to decide whether a contract between two parties could be enforced if it had been made in violation of an existing state law. The majority opinion held that such contracts were not enforceable and should be declared void by courts of justice. However, Justice Story wrote a dissenting opinion arguing that while he agreed with the majority's conclusion on this particular case, he believed that contracts which violated state laws should generally still be considered valid unless they contravened some fundamental principle or public policy. He argued that allowing people to enter into agreements without fear of them being invalidated would promote commerce and encourage individuals to engage in business transactions with confidence knowing their rights will remain protected even when there is a conflict between private interests and public regulations.