This language, from a Supreme Court case, would appear to be very encouraging to the United States Postal Service:
To decide the case we need look no further than the maxim that no man may take advantage of his own wrong. Deeply rooted in our jurisprudence this principle has been applied in many diverse classes of cases by both law and equity courts and has frequently been employed to bar inequitable reliance on statutes of limitations. In Schroeder v. Young. . ., this Court allowed a debtor to redeem property sold to satisfy a judgment, after the statutory time for redemption had expired although the statute granting the right to redeem also limited that right as to time. The Court held that the purchasers could not rely on the limitation because one of them had told the debtor ‘that he would not be pushed, that the statutory time to redeem would not be insisted upon; and (the debtor) believed and relied upon such assurance.’ The Court pointed out that in ‘such circumstances the courts have held with great unanimity that the purchaser is estopped to insist upon the statutory period, notwithstanding the assurances were not in writing, and were made without consideration, upon the ground that the debtor was lulled into a false security.’ As Mr. Justice Miller expressed it in Insurance Co. v. Wilkinson . . ., ‘The principle is that where one party has by his representations or his conduct induced the other party to a transaction to give him an advantage which it would be against equity and good conscience for him to assert, he would not in a court of justice be permitted to avail himself of that advantage. And although the cases to which this principle is to be applied are not as well defined as could be wished, the general doctrine is well understood and is applied by courts of law as well as equity where the technical advantage thus obtained is set up and relied on to defeat the ends of justice or establish a dishonest claim.’