In the case of Henry Webster v. Peter Cooper, Webster brought a suit against Cooper for breach of contract. The dispute arose from an agreement between the two parties in which Cooper was to pay Webster $1,000 for his services as a surveyor and engineer on certain lands owned by him. However, after completing his work, Webster did not receive payment from Cooper despite repeated requests. As such, he sought damages through legal action and argued that he had fulfilled all conditions necessary under their contract and thus deserved compensation for his labor. Ultimately, the Supreme Court found in favor of Webster ruling that since there was no evidence to suggest otherwise it must be assumed that both parties had complied with their obligations under the agreement; therefore they ordered Cooper to pay $1,000 plus interest due at 6% per annum until paid off in full as recompense for breaching said contract with Henry Webster.

In this case, the Supreme Court was asked to decide whether a contract between Henry Webster and Peter Cooper had been breached. The majority opinion held that the contract was valid and enforceable, but Justice McLean dissented from this decision. He argued that there were several ambiguities in the language of the agreement which made it impossible to determine what obligations each party had agreed to fulfill. Furthermore, he noted that even if one assumed all of its terms were clear, they could not be enforced because they violated public policy by attempting to limit competition among merchants in New York City. Finally, Justice McLean concluded that since no damages could be proven or calculated with any degree of certainty due to these issues with the contract itself as well as changes in market conditions over time since its formation, it would be unjust for either party to prevail on their claims against each other.