McKean Buchanan brought a case against James Alexander to the Supreme Court. The dispute was over an unpaid debt of $1,000 that had been loaned by Buchanan to Alexander in 1837. At the time of the loan, both parties agreed that if it were not paid back within two years then interest would be charged at 6%. When Alexander failed to pay back the money after two years, he claimed that no interest should have been applied because there was no written agreement specifying this term. However, Buchanan argued that verbal agreements are legally binding and therefore interest should still be due on top of repayment for principal amount borrowed. The Supreme Court ultimately sided with Buchanan and ruled in his favor; they held that verbal contracts are just as valid as written ones when it comes to financial obligations such as loans or debts.

In this case, the Supreme Court was asked to decide whether a contract between two parties could be enforced when one of those parties had died before it was completed. The majority opinion held that the contract could not be enforced because the deceased party's executor did not have authority to complete it. However, Justice McLean dissented from this ruling and argued that contracts should generally be enforceable even if one of the contracting parties has passed away prior to completion. He reasoned that since both sides had already agreed on all terms and conditions at issue in their agreement, there would be no harm in allowing its enforcement as long as any damages resulting from breach were appropriately compensated for by an estate or other legal representative of the deceased party. Furthermore, he noted that such a decision would help protect innocent third-parties who may rely upon these agreements without knowledge of either side's death or incapacity prior to performance being due under them.