Blennerhassett v. Sherman was a United States Supreme Court case that dealt with the issue of whether a party could be held liable for the actions of another party. The case involved a dispute between Blennerhassett and Sherman, two business partners who had entered into a contract to purchase a steamboat. Blennerhassett had agreed to pay Sherman a certain amount of money for the steamboat, but Sherman had failed to deliver the boat. Blennerhassett then sued Sherman for breach of contract. The Supreme Court held that Blennerhassett could not be held liable for the actions of Sherman. The Court reasoned that Blennerhassett had not been a party to the contract between Sherman and the steamboat seller, and thus could not be held liable for any breach of contract. The Court also noted that Blennerhassett had not been aware of the breach of contract, and thus could not be held liable for any damages resulting from the breach. In conclusion, the Supreme Court held that Blennerhassett could not be held liable for the actions of Sherman, and thus the case was dismissed. This decision established the principle that a party cannot be held liable for the actions of another party unless they are a party to the contract in question.

In Blennenrhett v. Sherman, the Supreme Court was tasked with determining whether a contract between two parties that had been made in violation of an existing state law could be enforced by either party. The majority opinion held that the contract was void and unenforceable due to its illegality under state law. However, Justice Field dissented from this opinion on the grounds that it would lead to unjust results for both parties involved in the contract dispute. He argued that if one party were allowed to benefit from their illegal actions while another suffered losses as a result of those same actions, then there would be no incentive for people not to engage in such activities going forward. Furthermore, he noted that allowing contracts formed illegally under state laws to stand would encourage individuals and businesses alike to enter into agreements without fear of repercussions or legal consequences should they fail or violate any applicable statutes along the way. Ultimately, Justice Field concluded his dissent by stating his belief that enforcing contracts formed unlawfully should remain within each individual state's discretion rather than being decided at a federal level like it had been done here