Educated at home by his father except for a few months at Braintree, he entered Harvard in 1796. There, he taught school in winter vacations. After graduating with high honors in 1800, he taught for a year in a Boston public school, and wrote articles and read proof for the Boston Gazette, a Federalist newspaper.
In August 1801, he began studying law in Boston under David Everett. Meanwhile, he learned French proficiently from a refugee, Antoine Jay, afterwards a founder in France of the liberal Constituionnel. In 1802, he moved with Everett to Amherst, New Hampshire, where besides doing legal work he contributed a poem on dancing and translations from French to the Farmers’ Cabinet, a local newspaper. He became engaged to Nancy Melville, daughter of Maj. Thomas Melville of Boston, the original of Holmes’s “The Last Leaf”, but she died soon afterwards.
Admitted to the bar in Hillsborough County, NH, in September 1804, and in Plymouth County, MA that November, he began practice in Boston. When his associate left Boston after being acquitted of murder in a political quarrel, he practiced alone for fifteen years. In about 1822, he took Sidney Bartlett, an able trial lawyer, as his junior partner. His practice gradually became large, but he was less known as an advocate than as the adviser of important commercial enterprises.
On January 6, 1818, he married Elizabeth Knapp, daughter of Josiah Knapp of Boston. She died in 1822, leaving a son and a daughter, Elizabeth, who became the wife of Herman Melville, the nephew of Shaw’s former fiancée. On August 29, 1827, he married Hope Savage, daughter of Dr. Samuel Savage of Barnstable; they had two sons.
Shaw was admirably prepared for his judicial career by numerous public positions. He was member of the Massachusetts House of Representatives in 1811-14, 1820 and 1829, a state senator in 1821-22, and a member of the constitutional convention of 1820. He also held many offices in Boston. In 1822, with few precedents to guide him, he drew the first charter of the city, which lasted until 1913. On the death of Chief Justice Isaac Parker, Governor Levi Lincoln offered Shaw the appointment. Though it meant giving up a practice of $15,00 to $20,000 a year for a salary of $3,500, he accepted. His commission was issued August 30, 1830, and he served 30 years, resigning August 21, 1860.
His exceptionally long judicial career coincided with the development of many important industries, so that his great abilities had full scope for making the law on such matters as water power, railroads and other public utilities. Probably no other state judge has so deeply influenced commercial and constitutional law throughout the nation. Almost all the principles laid down by him have proved sound, although his remarkable skill in expounding the fellow-servant rule considerably delayed the replacement of that rule by workmen’s compensation.
An opinion by Shaw rarely lends itself to isolated quotations; its strength lies in the entire solidity of its reasoning. “His words had weight rather than brilliancy or eloquence”, and his greatness came from his personality as well as from his intellectual powers. He was no mere writer of opinions, but preeminently a magistrate.
In Shaw’s time, the Chief Justice sat often at trials. In such work he was thorough, systematic, very patient, with a remarkable power to charge juries so that they understood the exact questions before them. Among his cases that excited great public interest were the trial in 1834 of the anti-Catholic rioters who destroyed the Ursuline convent in Charlestown (Commonwealth v. Buzzell); the 1847 divorce case of Henry Cobb against his wife Augusta Adams Cobb for committing adultery with Mormon leader Brigham Young (Cobb v. Cobb); and that in 1850 of Prof. John White Webster for murdering George Parkman (Commonwealth v. Webster). In 1851, he refused to release Thomas Sims, the fugitive slave, on habeas corpus; he was strongly opposed to slavery, but he felt bound by the Constitution and the law, and disregarded both the violence of the mob and the denunciations of the respectable regarding his opinion.
Shaw's work in extending the equity, jurisdiction, and powers of the court was especially important. He also was largely instrumental in defeating an attempt in 1843 to make a reduction of salary apply to judges already in office and an attempt by the Massachusetts Constitutional Convention of 1853 to abolish the life term of judges. His opinion in Cary v. Daniels (8 Metcalf) was an important legal precedent in Massachusetts regarding the regulation of water power rights belonging to riparian proprietors. His ruling in favor of the constitutionality of school segregation in Roberts v. City of Boston (1849) established "separate but equal" as a legal doctrine.
In Commonwealth v. Hunt (1842), Shaw provided an important precedent in labor relations by arguing that members of labor unions were not engaging in criminal conspiracies against their employers. His decision in Commonwealth v. Alger (1851) was an early and influential attempt to define the limits of state police power. In Brown v. Kendall (1850), Shaw established negligence as the dominant standard of tort law, and ruled that injured plaintiffs have the burden of proving that the defendant was negligent.
Widely read in English literature, he was also attracted by new mechanical processes and was a member of many learned and charitable societies. He was a fellow of Harvard College from 1834 until his death, and an overseer from 1831 to 1853, two offices rarely united.
In politics he was a Federalist and a Webster Whig, but remained all his life a free-trader. He attended Unitarian services, though he was never a communicant. Fond of entertaining and dining out, he was simple and affectionate in his home life, his interest in the social events of his household extending to the minutest details. After his resignation from the bench, his health failed, and he died within a few months. He was buried in Mount Auburn Cemetery.