He was elected as county attorney in Ramsey County in 1892, and re-elected in 1894. Butler joined the law firm of How & Eller in 1896, which became How & Butler after the death of Homer C. Eller the following year. He accepted an offer to practice in St. Paul, Minnesota, where he took care of railroad-related litigation for James J. Hill. He was highly successful in representing railroads. In 1905 he returned to private practice and rejoined Jared How. He had also served as a lawyer for the company owned by his five brothers. In 1908, Butler was elected President of the Minnesota State Bar Association. From 1912 to 1922, he worked in railroad law in Canada, alternately representing the shareholders of railroad companies and the Canadian government; he produced favorable results for both. When he was nominated for the United States Supreme Court in 1922, Butler was in the process of winning approximately $12,000,000 for the Toronto Street Railway shareholders.
Nomination and confirmation
Although he was supported by Chief Justice and former President William Howard Taft, Butler's opposition to "radical" and "disloyal" professors at the University of Minnesota made him a controversial Supreme Court nominee when proposed by Republican President Warren Harding. The Senator-elect Henrik Shipstead of his home state opposed him, as did the ProgressiveSenator Robert M. La Follette Sr. of Wisconsin. Also against his confirmation were labor activists, some liberal magazines and the Ku Klux Klan because he was Catholic. However, with the support of prominent Roman Catholics, fellow lawyers, and business groups, as well as Minnesota's other senator Knute Nelson, Butler was confirmed on Dec 21, 1922, by a margin of 61 to 8. The Senators who voted against him were five Democrats and three Republicans. He took his seat on the Court on January 2, 1923.
Court service
As an Associate Justice, Butler vigorously opposed regulation of business and the implementation of welfare programs by the federal government. During the Great Depression, he ruled against the constitutionality of many "New Deal" lawsthe Agricultural Adjustment Administration and the National Recovery Administrationwhich had been supported by his fellow Democrat Franklin D. Roosevelt. This earned him a place among the so-called "Four Horsemen," which also included James Clark McReynolds, George Sutherland, and Willis Van Devanter. During his sixteen years on the bench, Justice Butler authored 327 majority opinions as well as 50 minority opinions. He wrote the majority opinion in United States v. Schwimmer, in which the Hungarian immigrant's application for citizenship was denied because of her candid refusal to take an oath to "take up arms" for her adopted country. In Palko v. Connecticut, Butler was the lone dissenter on the court; the rest of the justices believed that a state was not restrained from trying a man a second time for the same crime. Butler believed this violated the Fourteenth Amendment to the United States Constitution. He sided with the majority in Pierce v. Society of Sisters, holding unconstitutional an Oregon state law which prohibited parents from sending their children to private or religious schools. In the 1927 decision for Buck v. Bell, Butler was the only Justice who dissented from the 8–1 ruling and Justice Oliver Wendell Holmes, Jr.'s opinion holding that the forced sterilization of an allegedly "feeble-minded" woman in Virginia was constitutional. Holmes believed that Butler's religion influenced his thinking in Buck, remarking that "Butler knows this is good law, I wonder whether he will have the courage to vote with us in spite of his religion." Although Butler dissented in both Buck and Palko, he did not write a dissenting opinion in either case; the practice of a Justice's noting a dissent without opinion was much more common then than it would be in the later 20th and early 21st centuries. Another consequential dissent was from the opinion expressed in Olmstead v. United States which upheld federal wiretapping. He took an expansive view of 4th Amendment protections.
Death and legacy
On November 15, 1939, Butler went into the hospital for "a minor ailment" but died in the early morning hours of November 16. He died in Washington, D.C., at the age of 73 while still on the court. He was the last serving Supreme Court Justice appointed by President Harding. He is buried in Calvary Cemetery in St. Paul. Justice Butler is one of 13 Catholic Justicesof 113 total Justices in the history of the Supreme Court. of his and his family's collected papers are with the Minnesota Historical Society. Other papers are collected elsewhere. Pierce Butler Route in Saint Paul, Minnesota, is named in honor of Butler.
