Justice Clifford was born in Rumney, New Hampshire, though he ultimately spent much of his professional life in Maine, the state from which he would be appointed to the Supreme Court of the United States. He did not receive any formal university education, which was not uncommon for his era.
In 1827, Justice Clifford entered private practice in Newfield, Maine, a town just west of Portland, Maine, and worked continuously as a private attorney until 1830, when he joined the Maine House of Representatives. He remained in that body for four years, the last two of which he served as Speaker, before starting a four-year term as the Attorney General of the state of Maine. In 1839, one year after Justice Clifford left that office, he became a Member of the United States House of Representatives from Maine, serving until 1843, when he returned to private practice in Newfield. Three years later, he took office as the Attorney General of the United States, where he remained from 1846 to 1848, when he started a one-year term as Minister to Mexico on behalf of the United States Department of State. Justice Clifford then returned to private practice for the final time, now in Portland, and worked there continuously from 1849 until his appointment to the SCUS.
Justice Clifford was nominated by President James Buchanan on December 9, 1857, to a seat vacated by Justice Benjamin Robbins Curtis. He was confirmed by the United States Senate on January 12, 1858, and received his commission that day. Justice Clifford took the Judicial Oath to officially join the SCUS on January 21, and served on the Taney, Chase, and Waite Courts. His service was terminated on July 25, 1881, due to his death.
Justice Clifford served during one of the most pivotal eras in SCUS history. While he was not a particularly prominent leader of the Court in his time, he took part in some incredibly important cases that helped establish how the Court would interpret the newly-passed Civil War Amendments for decades to come, such as The Slaughterhouse Cases (1873), where he joined the opinion of the Court in declaring that some state-initiated monopolies were not precluded by the 13th or 14th Amendments. Justice Clifford is also known for having chaired the commission that was tasked with settling the disputes over the Presidential Election of 1876, and was famously displeased when he was outvoted by its Republican members. Justice Clifford was so upset by his side’s defeat, in fact, that he is said to have refused to set foot in the White House while President Rutherford B. Hayes, the eventual winner of that disputed election, was in office. He suffered a stroke in 1880, but supposedly refused to retire as long as the hated President Hayes, or any other Republican, could choose his successor; he was able to live long enough to ensure the former, though his death in 1881 meant that the latter wish went unfulfilled.