Matthew Hale Carpenter (born Decatur Merritt Hammond Carpenter; – ) was an American lawyer, politician, and Wisconsin pioneer. He represented Wisconsin for eight years as a United States senator, from 1869 to 1875 and again from 1879 until his death in 1881. He was recognized as an authority on constitutional law, and made some of the most important legal arguments of 19th-century America, presenting several cases before the United States Supreme Court involving such matters as states' rights and regulation of corporations; during the American Civil War, he argued many important cases establishing the legal framework for President Abraham Lincoln's war powers and the postwar Reconstruction Acts.

Originally a Democrat, he evolved into a Republican during the Civil War, and helped perpetuate the party's political machinery in Wisconsin. His sustained support for President Ulysses S. Grant's administration despite allegations of corruption lost him the backing of reformers, and his legal arguments in favor of Democratic candidate Samuel J. Tilden in the disputed presidential election of 1876 outraged many Republicans. A gifted orator, he was dubbed "the Webster of the West."

Background and education Carpenter was born in Moretown, Vermont, in the Mad River Valley of the Green Mountain range. His pioneering forebears were English, and came to America soon after the Pilgrims. His grandfather Cephas Carpenter (1770–1860) helped establish Moretown, owned a store, served as a colonel in the militia and took part in the War of 1812. Cephas Carpenter served in local office including justice of the peace, and though not a member of the bar, possessed wisdom and eloquence that led to a career as an advocate in the local courts.

His son Ira Carpenter (1798–1862) was chiefly a farmer, but he also gained prominence through positions such as justice of the peace, postmaster and state legislator.

Grandson Merritt displayed intelligence and oratorical talents at an early age, impressing people with his abilities to recite Cicero and exhort at religious revivals. He also displayed an aversion to physical work.Thompson, p.3–10

After an explosive argument with a schoolmaster, the 13-year-old Carpenter was expelled from school. He was dissatisfied with the limits of Moretown, and left home to live and study law under the tutelage of family friend (and future Vermont governor) Paul Dillingham in nearby Waterbury. For four years Carpenter attended the local grade school while absorbing Dillingham's law library. Having received an appointment to the United States Military Academy through Vermont Congressman John Mattocks, Carpenter continued his studies, but he disliked military life and resigned in August 1845, citing poor health.Thompson, pp. 11-15.

He returned to live in Dillingham's home and managed his law office while Dillingham was then a congressman in Washington, D.C. Upon Carpenter's admission to the Vermont bar in November 1847 Dillingham offered to make him his law partner, but Carpenter declined so he could further his law studies under Rufus Choate of Boston. Choate was also impressed with Carpenter, and after a few months he too offered him a partnership, but Carpenter sought to make a name and career for himself in the West.Thompson, pp. 15-21.

Wisconsin attorney After reading that the territory of Wisconsin had passed its constitution and was soon to become a state, Carpenter chose to migrate west and begin his career as a lawyer in Beloit on the endorsement of that spot by the New England Emigrating Society's Dr. Horace C. White. Arriving in June 1848, Carpenter quickly established a reputation as a successful and affordable attorney, attracting much acclaim from the local community.

His practice was interrupted by a painful inflammation of his eyes which rendered him blind. After traveling to New York to seek treatment, his sight gradually recovered after a year as he convalesced in the Waterbury home of his mentor Dillingham. Before returning to Wisconsin he became engaged to Dillingham's daughter Catherine, and they married five years later.Thompson, pp. 21-29.

In 1850 Carpenter returned to resume his law practice in Beloit using a new name, Matthew (Matt) Hale Carpenter, after Sir Matthew Hale, the noted English jurist of the 17th century.Thompson, pp. 33-34. Despite an earlier warning from Choate to steer clear of politics, Carpenter successfully ran for Rock County district attorney, serving from 1850 to 1852 and 1854 to 1856. He was a Democrat in the tradition of Thomas Jefferson and Andrew Jackson, but he disdained the party's pro-slavery platform while also rejecting Whig Party notions of opposing slavery based on "higher law"—the idea that individual belief of right and wrong permitted an individual to violate objectionable statutes and ordinances.Thompson, pp. 31-33. After appearing to lose a close election for another term as Rock County district attorney in 1854, Carpenter successfully argued that courts could look beyond election board certifications and re-examine voter returns, resulting in the election being overturned.Thompson, p. 35.

Gardner v. Tisdale In 1855, Carpenter discovered that many Beloit residents did not hold legal title to their land because it was sold to them by someone who had pre-empted the land but had not received official title from the government (Congress had previously outlawed the pre-emption of non-agricultural land). Carpenter put forth the theory that the original pre-emptor was still technically the owner of the property. After several complicated transactions, some of which included Paul Dillingham selling new titles to the landowners, and appeals as far as the United States Supreme Court, which included participation by Dillingham, Rufus Choate, Abraham Lincoln and other prominent attorneys, Carpenter's legal theory was rejected in a similar case, so the Wisconsin case was withdrawn.Thompson, pp. 37-39.

Barstow-Bashford election dispute Wisconsin's gubernatorial election of 1855 was thrown into doubt when incumbent Democratic governor William A. Barstow was ruled the 157-vote victor over Republican Coles Bashford by a board of canvassers friendly to Barstow. Discrepancies were discovered in the election returns and political tensions rose as both parties claimed the office and swore in their candidates. Hired by Barstow, Carpenter stalled by repeatedly postponing the case before the state supreme court. He claimed that they held no jurisdiction because elections were matters of the executive branch, which had ruled Barstow the winner. Nevertheless, the court did claim jurisdiction and the ability to examine election tallies (as Carpenter had previously argued for his own election for district attorney). Barstow then resigned, elevating Lieutenant Governor Arthur MacArthur to the governorship. After the court ruled that Bashford was the rightful governor, MacArthur gave up the office. Barstow subsequently refused to pay Carpenter his fee.Thompson, pp. 40-45.

Despite his defeat Carpenter had demonstrated his legal prowess to the state. A high volume of his cases required his presence in federal court in Milwaukee, leading to him locating his practice there in 1858. He was also coaxed there by Democratic party boss Josiah Noonan, who arranged a law partnership between Carpenter and Edward G. Ryan, another highly regarded attorney and a force in the state Democratic Party. Despite their excellent credentials, they proved to be temperamentally incompatible, and ended their partnership the next year.Thompson, pp. 46-52. Among the prospective attorneys who studied law under Carpenter in Milwaukee was Lyman W. Redington.

By the time Carpenter moved to Milwaukee he had become adept in the area of railroad litigation and sued many railroads on behalf of investors left holding bonds made worthless by fraudulent manipulation. His debut before the U.S. Supreme Court resulted in his winning a judgment against the La Crosse and Milwaukee Railroad Company.Thompson, pp. 54-61. He was also successful as part of a team of lawyers defending abolitionist Sherman Booth from a charge of rape.Thompson, pp. 61-62.

Loyal Democrat during the Civil War Carpenter supported Democrat Stephen Douglas in the 1860 presidential election, viewing Republican Abraham Lincoln as an honest but incompetent sectional candidate. Yet, he warned those in his party that he saw secession as treason, and he would be "the first man to raise a musket" in defense of the Constitution.Thompson, pp. 62-63. Following the Confederates' attack on Fort Sumter in 1861, Carpenter did not enlist but became a rousing speaker in support of the Union cause.Thompson, p. 65.

While he saw that many federal actions would be unconstitutional in peacetime, he reasoned that arbitrary arrests and suspensions of habeas corpus were acts of self-preservation during wartime and thereby permitted.Thompson, pp. 64-65. He also became an early advocate for emancipation, but only as a war measure rather than an act of humanity.Thompson, p. 66. Excluded from meetings of the Democratic leadership, Carpenter joined other like-minded party members of the "Loyal Democracy" in considering a third party in Wisconsin, but nothing came of it.Thompson, pp. 72-78.

Personal letters he had written saying Lincoln was "idiotic" found their way into newspapers, but Carpenter supported him for re-election in 1864 by making numerous pro-Union and pro-Lincoln speeches.Thompson, pp. 79-82.

Defining the Reconstruction Acts Carpenter was the key attorney in a series of landmark cases before the U.S. Supreme Court which helped define states' rights by determining the legality of the Reconstruction acts passed by Congress.

Ex parte Garland dealt with the disbarment from federal courts of Southern lawyers who refused to take an oath swearing they had not taken up arms or assisted the Confederacy. Carpenter argued that the act passed on January 24, 1865, was ex post facto (the war had since ended) and a bill of attainder (it punished without a trial). In December 1865 the court upheld his argument with the majority opinion employing phrases from Carpenter's brief.Thompson, pp. 89-90.

Ex parte McCardle concerned the legal authority of the occupying Union Army. Confederate Colonel William H. McCardle, the editor of the Vicksburg Times, was charged with defying military authority by inciting rebellion, libeling federal officials, and intimidating voters. After the circuit court denied him a writ of habeas corpus, McCardle appealed to the Supreme Court of the United States. Carpenter argued that the court lacked jurisdiction over a president's official acts, as in a similar case of his, Georgia vs. Grant. Rather than claiming the Union's "right of conquest," Carpenter said the Southern states had surrendered their constitutional protections when they had seceded, essentially reverting to territories.Thompson, pp. 91-98.

After he concluded his eloquent arguments, Secretary of War Edwin Stanton hugged him, declaring "Carpenter, you have saved us!" Even McCardle's attorney Jeremiah S. Black lauded him as "the first Constitutional lawyer in the country." However, Radical Republicans in Congress feared that the reconstruction acts would be ruled unconstitutional, so they quickly pushed through a law repealing the Habeas Corpus Act of 1867, barring jurisdiction in pending cases and preventing a clear decision from being rendered by the court.Thompson, pp. 98-99.