United States Supreme Court Associate Justice. A member of the Whig Party, he served in this position from September 1851 until September 1857 and is remembered as one of the two High Court dissenters in the famous Dred Scott v. Sanford (1857) decision. He was the first appointed Justice to have earned a law degree from a law school. Born in Watertown, Massachusetts his father worked as a captain on a merchant vessel. After attending Harvard College, then Harvard Law School in Cambridge, Massachusetts from which he graduated in 1831, he was admitted to the bar and joined the Boston, Massachusetts law firm of Charles P. Curtis Esquire. In 1846 he was one of the attorneys who argued for the defense in the Commonwealth v. Aves lawsuit, that involved a young slave girl who was voluntarily brought into Massachusetts by her owner and was ultimately set free by the Massachusetts Supreme Court. In 1849 he was elected to the Massachusetts House of Representatives. In September 1851 he was nominated to the US Supreme Court by President Millard Fillmore, to fill the seat vacated by the death of Associate Justice Levi Woodbury, and was confirmed by the US Senate the following December. Probably the most important case the Supreme Court heard while he was on the bench was Dred Scott v. Sanford (1857). As an anti-slavery proponent, he argued against the High Court's denial for Scott's emancipation, contending there were African American citizens in the North and South at the time and were considered by the United States Constitution as "people of the United States." In September 1857 he resigned from his seat on the High Court as a matter of principle, due to his bitterness over the Dred Scott case, and was replaced by Nathan Clifford. He then returned to his private law practice in Boston. In 1868 he served as chief counsel who successfully defended President Andrew Johnson during his impeachment trial in the US Senate. After the trial, Johnson offered him the position of US Attorney General but he declined. Following the death of Massachusetts US Senator Charles Sumner in March 1874, he sought to be his replacement as a Democrat but the Massachusetts state senate chose Republican Governor William B. Washburn to fill the vacant seat. He died in Newport, Rhode Island at the age of 64.