Benjamin Robbins Curtis (November 4, 1809 – September 15, 1874) was an American attorney and United States Supreme Court Justice.

Curtis was the first and only Whig justice of the Supreme Court. He was also the first Supreme Court justice to have a formal legal degree and is the only justice to have resigned from the court over a matter of principle. He successfully acted as chief counsel for President Andrew Johnson during the first presidential impeachment trial.

Benjamin Curtis was born November 4, 1809 in Watertown, Massachusetts, the son of Lois Ribbins and Benjamin Curtis, the captain of a merchant vessel. Young Curtis attended common school in Newton and beginning in 1825 Harvard College, where he won an essay writing contest in his junior year. He graduated in 1829, a member of Phi Beta Kappa. He subsequently graduated from Harvard Law School in 1831 and was admitted to the bar the following year.

In 1834, he moved to Boston where he joined the law firm of Charles P Curtis Esquire.

In 1836, Curtis participated in the Massachusetts "freedom suit" of Commonwealth v. Aves on behalf of the defendant. When New Orleans resident Mary Slater went to Boston to visit her father, Thomas Aves, she brought with her a young slave girl about six years of age, named Med. While in Boston, Slater fell ill and asked her father to take care of Med until she (Slater) recovered. The Boston Female Anti - Slavery Society and others sought a writ of habeas corpus against Aves, contending that Med became free by virtue of her mistress' having brought her voluntarily into Massachusetts. Aves responded to the writ, answering that Med was his daughter's slave, and that he was holding Med as his daughter's agent. Curtis was one of the attorneys who argued the case on behalf of Aves.

The Supreme Judicial Court of Massachusetts, through its Chief Justice, Lemuel Shaw, ruled that Med was free, and made her a ward of the court. The Massachusetts decision was considered revolutionary at the time. While previous decisions ruled that slaves voluntarily brought into a free state, and who resided there many years, became free, Aves was the first decision which held that a slave voluntarily brought into a free state became free from the first moment of arrival. The decision in this freedom suit engendered controversy and helped to alienate the South. It was in contrast to the Dred Scott decision, in which Curtis participated as an Associate Justice of the Supreme Court.

Curtis became a Harvard Fellow in February 1846. In 1849, he was elected to the Massachusetts House of Representatives. Appointed chairman of a committee to reform state judicial procedures, they presented the Massachusetts Practice Act of 1851. "It was considered a model of judicial reform and was approved by the legislature without amendment."

At the time, Curtis was viewed as a rival to Rufus Choate, and was thought to be the preeminent leader of the New England bar. He came from a politically connected family, and had studied under Joseph Story and John Hooker Ashmun at Harvard Law School. His legal arguments were thought to be well - reasoned and persuasive. He was a Whig and in tune with their politics, and Whigs were in power. As a potential young appointee, he was thought to be the seed of a long and productive judicial career. He was appointed by the president, approved by the Senate, elevated to the bench, but was gone in six years.

Curtis received a recess appointment to the Supreme Court on September 22, 1851 by President Millard Fillmore, filling the vacancy caused by the death of Levi Woodbury. Massachusetts Senator Daniel Webster persuaded Fillmore to nominate Curtis to the Supreme Court, and was his primary sponsor. Formally nominated on December 11, 1851, Curtis was confirmed by the United States Senate on December 20, 1851, and received his commission the same day. He was elected a Fellow of the American Academy of Arts and Sciences in 1854.

He was the first Supreme Court Justice to have earned a law degree from a law school — his predecessors had either "read law" (a form of apprenticeship in a practicing firm) or had attended a law school without receiving a degree.

His opinion in Cooley v. Board of Wardens 53 U.S. 299 (1852) held that the Commerce Power extends to laws related to pilotage. States laws related to commerce powers can be valid so long as Congress is silent on the matter. This resolved a historic controversy over federal interstate commerce powers. To this day, it is an important precedent for resolving disputes. The court interpreted Art. I, section 8, clause 3 of the Constitution, the Commerce Clause. The issue was whether states could regulate aspects of commerce or whether Congress retained exclusive jurisdiction to regulate commerce. Curtis concluded that the federal government enjoyed exclusive power to regulate commerce only when the thing regulated required national uniformity. Otherwise, states were permitted to regulate commerce.

Curtis was notable as one of the two dissenters in the Dred Scott case, where he disagreed with virtually every holding of the court, and argued against the majority's denial of the slave Scott's bid for emancipation. See, dissenting opinion of Justice Benjamin Curtis, wherein he stated that there were African American citizens in both Southern and Northern at the time: Therefore, they were among the "people of the United States" whom the Constitution addressed. Curtis also opined that since the majority had found that Scott lacked standing, the Court had no power to rule on the merits of his case.

Curtis resigned from the court on September 30, 1857, because of the bitter feelings engendered by the Scott case. His bitterness over the decision was said to be compounded by displeasure over his salary.

Others view the cause of his resignation as having been temperamental and financial. He did not like "riding the circuit" as Supreme Circuit Justices were then required to do. He was temperamentally estranged from the court, and was not inclined to work with others — he was not a 'team player', at least not on that team. The acrimony over the Dred Scott decision had blossomed into mutual distrust. He did not want to live on $6,500 per year, an amount much less than his earnings in private practice. Finally, the public outcry over his decision was contrary to his elitist inclinations, as he thought the public was not supposed to talk back.

Another source states, “a bitter disagreement and coercion by Roger Taney prompted Benjamin Curtis's departure from the Court in 1857."

"Although he remained on the Court for only six years, Curtis is generally considered to have been the only outstanding justice on the Taney Court in its later years, other than Taney himself." He is the only Justice of the Supreme Court to have resigned on a matter of principle.

Upon his resignation, Curtis returned to his Boston law practice, becoming a "leading lawyer" in the nation. During the ensuing decade and a half, he argued several cases before the Supreme Court.

In 1868, Curtis acted as chief counsel for President Andrew Johnson during the impeachment trial. He read the answer to the articles of impeachment, and it was "largely his work." His opening statement lasted two days, and was commended for legal prescience and clarity. He successfully persuaded the Senate that an impeachment was a judicial act, not a political act, so that it required a full hearing of evidence. This precedent "influenced every subsequent impeachment."

After the impeachment trial, Curtis declined President Andrew Johnson's offer of the position of U.S. Attorney General. A highly recommended candidate for the Chief Justice position upon the death of Salmon P. Chase, Curtis did not receive the appointment. He was the unsuccessful Democratic candidate for U. S. senator from Massachusetts in 1874. From his retirement from the bench in 1857 to his death in 1874, his aggregate professional income was about $650,000.

Curtis died in Newport, Rhode Island, on September 15, 1874. He is buried at Mount Auburn Cemetery, 580 Mount Auburn Street, Cambridge, Massachusetts.

Curtis' daughter, Annie Wroe Scollay Curtis, married (on December 9, 1880) future Columbia University President and New York Mayor, Seth Low. They had no children.