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After the breaking out of the Civil War Congress was compelled in 1862 to issue $150,000,000 in Treasury notes, and made them legal tender for payment of private debts and all public dues except duties on imports and interest on the public debt. These notes became the circulating medium to a large extent. The constitutional validity of these Legal-Tender Acts was strongly contested, especially in their application to debts contracted prior to their passage. Their constitutionality was generally maintained by the State courts, however. In 1869, this question came before the Supreme Court of the United States in the case of Hepburn vs. Griswold. The validity of the acts was in this instance maintained only in so far as it did not affect the obligations of contracts made prior to their passage. A year later, in the case of Knox vs. Lee, this decision was overruled, and the constitutionality of the act was upheld in its applicability to preexisting debts, though by a majority of the court only. The composition of the court had meantime been altered, two new judges having been appointed. See Hepburn vs. Griswold, Knox vs. Lee, and Juilliard vs. Greenman.