As both secretary of the Navy and attorney general in Roosevelt's cabinet, Moody sought to creatively reform both departments in the spirit of Progressivism.

William Henry Moody was born in Newbury, Massachusetts, on December 23, 1853, attending local schools in Danvers, Massachusetts, before graduating from Phillips Academy in 1872. Four years later, he earned his bachelor's degree in history from Harvard University, after which he spent less than a year at Harvard Law School. Moody was district attorney for Eastern Massachusetts from 1890 to 1895, when he won a seat on the U.S. House of Representatives. He served in Congress from November 1895 to May 1902. Following the resignation of John Davis Long on March 10, 1902, Senator Henry Cabot Lodge recommended Moody for the position of naval secretary. Moody served in that post until he became attorney general following the resignation of Philander C. Knox in June 1904. Moody would go on to prosecute more monopolies than any other attorney general under both criminal and civil provisions of the Sherman Antitrust Act. He was intending to return to private life when Supreme Court Justice Henry Billings Brown retired; President Roosevelt appointed Moody to serve on the Supreme Court. Moody was considered a "pillar of judicial restraint" while on the bench, serving between December 1906 and November 1910. He died at his home in Haverhill, Massachusetts, on July 2, 1917.