In Bank of the United States v. Dunn (1832), 31 U.S. 51, the Supreme court decided that Carr, who was an indorser after Dunn, was not competent to prove facts which would tend to discharge Dunn from the responsibility of his indorsement. It was held that an agreement by the president and cashier that the indorser on a note shall not be liable on his indorsement does not bind the bank; that it is not the duty of the cashier and president to make such contracts, nor have they the power to bind the bank, except in the discharge of their ordinary duties.In that case the court said, "it is a well settled principle, that no person who is a party to a negotiable instrument, shall be permitted, by his own testimony, to invalidate it." It was decided that no man who was a party to a negotiable instrument, should be permitted, by his own testimony, to invalidate it. It was also held that the power to discount paper was not one of the implied powers of the cashier,