In the case of Robert Barnwell Rhett v. Robert F. Poe, Cashier of the Bank of Augusta, Rhett was suing for a debt that he claimed to be owed by Poe and the Bank of Augusta. The court found in favor of Poe and the bank on grounds that there was no evidence presented to prove that any debt existed between them or had been contracted at all. Furthermore, it was determined that even if such a contract did exist, it would have been void due to an act passed by Congress which prohibited state banks from issuing notes payable after demand unless they were secured with United States stocks or other approved securities; this act had not been complied with in this instance as no security had been provided for said note issued by the bank. Ultimately, Rhett's claim against Poe and the Bank failed as his suit could not be sustained without proof being offered up firstly establishing its existence and secondly showing compliance with federal law regarding such contracts made between state banks and their customers.

In the case of Robert Barnwell Rhett v. Robert F. Poe, Cashier of the Bank of Augusta, Justice McLean delivered a dissenting opinion in which he argued that the bank had no right to set off its debt against deposits made by Rhett with it. He reasoned that since there was no contract between them allowing for such an action, and because banks are not allowed to engage in any other business than banking without special permission from their state legislature, they could not lawfully exercise this power over customers' funds deposited with them. Furthermore, Justice McLean noted that even if such a contractual agreement did exist between parties involved in this dispute - as was suggested by Chief Justice Taney's majority opinion - then it would be void under Georgia law due to its being contrary to public policy and interest; thus making it impossible for either party to enforce or benefit from such an arrangement. In conclusion, he concluded that while banks may have some rights when dealing with their own debts owed by customers who deposit money with them; those rights do not extend so far as setting off one debt against another without express authorization from both parties involved or explicit permission granted through legislation passed at the state level.