In another civil rights case in 1854, Arthur was the lead attorney representing Elizabeth Jennings Graham, a woman who was denied a seat on a streetcar because she was black. Arthur successfully argued the case for his client, and the verdict led to the desegregation of the New York City streetcar lines.
In 1856, Arthur started a new law partnership with a friend, Henry D. Gardiner, and traveled with him to Kansas to consider purchasing land and setting up a law practice there. At that time, Kansas was the scene of a brutal struggle between pro-slavery and anti-slavery forces, and Arthur lined up firmly with the latter. But the rough frontier life did not agree with the genteel New Yorkers and after three or four months the two young lawyers returned to New York City.
When the Civil War began in April 1861, Arthur was given the rank of brigadier general and assigned to the quartermaster department. He was so efficient at housing and outfitting the troops that poured into New York City that he was promoted within the state militia to inspector general in February 1862, and then to quartermaster general in July. The closest Arthur came to the front was when he traveled south to inspect New York troops near Fredericksburg, Virginia, in May 1862, shortly after forces under Major General Irwin McDowell seized the town during the Peninsula Campaign. Arthur's position was a political one, and he was relieved of his office in January 1863 when Governor Horatio Seymour, a Democrat, became Governor of New York.
Arthur had been a supporter of powerful New York Senator Roscoe Conkling and his supporters known as "Stalwarts." The Stalwarts believed in rewarding their supporters with patronage positions, while opponents of the Stalwarts like JamesGarfield, believed on doling out government appointments based on merit, regardless of political affiliation. But when Garfield was chosen as the Republican nominee for President in 1880, as a compromise candidate for a deadlocked convention, he knew he would face a difficult election without the support of the New York Stalwarts, so he decided to offer Arthur the vice presidential nomination. Conkling told Artrhur to reject the nomination, but to his credit Arthur was his own man and accepted, telling Conkling, "The office of the Vice-President is a greater honor than I ever dreamed of attaining." Several months later, President Garfield died in office as the result of being shot by Charles Guiteau and Arthur became President on September 22, 1881.
Like his Republican predecessors, Arthur struggled with the question of how his to protect the civil rights of African-Americans in southern states. Conservative white Democrats had regained power in the South, and the Republican party dwindled rapidly as their primary supporters in the region, African-Americans, were becoming disenfranchised. Garfield had gained some support in Virginia on a platform of more education funding (for black and white schools alike). Arthur directed federal patronage in Virginia to breakaway segments of the Democratic party that had supported Garfield. Some African-American Republicans felt betrayed by this tactic, but others like Frederick Douglass endorsed the administration's actions, because the Southern independents had more liberal racial policies than the Democrats. Arthur's coalition policy was only successful in Virginia.
Arthur tried other action on behalf of African-Americans, but when the Supreme Court struck down the Civil Rights Act of 1875 in an 1883 decision, Arthur's efforts were hampered. He expressed his disagreement with the decision in a message to Congress, but was unable to persuade Congress to pass any new legislation in its place.
Arthur was able to intervene to overturn a court-martial ruling against a black West Point cadet, Johnson Whittaker, after the Judge Advocate General of the Army, David G. Swaim, found the prosecution's case against Whittaker legally invalid and based on racial bias.
Arthur faced a different challenge in the West, where the Mormon Church was under government pressure to stop the practice of polygamy in the Utah Territory. Garfield had believed polygamy was criminal behavior and was morally detrimental to family values, and Arthur's concurred. In 1882, he signed the Edmunds Act into law, making polygamy a federal crime and barring polygamists from public office.
The Arthur administration also dealt with changing relations with western American Indian tribes. The Indian Wars were winding down, and public sentiment was shifting toward more favorable treatment of Native Americans. Arthur urged Congress to increase funding for Indian education, which it did in 1884, although not to the extent he wished. He also favored a move to the allotment system, under which individual Native Americans, rather than tribes, would own land. Arthur was unable to convince Congress to adopt the idea during his administration but, in 1887, the Dawes Act changed the law to favor such a system. The allotment system was favored by liberal reformers at the time, but eventually proved detrimental to Native Americans as most of their land was resold at low prices to white speculators.
Arthur was diagnosed with a kidney disease and his health prevented him from running for re-election. It was unfortunate that Arthur's health and his lack of political support prevented him from implementing the progressive civil rights reforms that he would have liked to. In many areas Arthur turned out to be a pleasant surprise as president and one of these was in the field of civil rights.