Joseph C. Pelletier (April 25, 1872 – March 25, 1924[1]) was district attorney of Suffolk County, Massachusetts, the first owner and president of the Boston Red Sox,[2] and the Supreme Advocate of the Knights of Columbus.

[5] He provided legal advice to the Order as Supreme Advocate for 15 years, from 1907 to 1922,[5][3] He also served as a member of the Knights of Columbus Commission on Religious Prejudice.

[9] France awarded Pelletier the Legion of Honor and Belgium made him a Knight of the Crown for his services during the war.

"[2][12] In 1904, Pelletier transferred six of his shares to John I. Taylor, the son of the Boston Globe publisher who owned the Red Sox from 1904 until 1911.

[4][3] He easily defeated Edward P. Barry, Felix W. McGettrick, and Alonzo D. Moran at the county convention to win the Democratic nomination (receiving 149 of the necessary 117 votes on the first ballot) and beat Republican incumbent Arthur D. Hill in the general election.

[21] In 1917, Pelletier petitioned Governor Samuel W. McCall for leniency in the treatment of Jesse Pomeroy, who had been living in solitary confinement at the Charlestown State Prison for more than 40 years.

[27] After a complaint to the state legislature's Joint Judiciary Committee was dismissed in the winter of 1916, the society went to the Massachusetts Supreme Judicial Court, which twice found their charges unworthy of a hearing.

He traced the wires back to an office paid for by Godfrey Lowell Cabot, president of the Watch and Ward Society.

[28] On September 29, 1921, the Boston Bar Association recommended to Massachusetts Attorney General J. Weston Allen that Pelletier be removed from office, alleging that he was guilty of deceit, malpractice, and gross misconduct.

Late in the trial, former Middlesex County district attorney William J. Corcoran turned state's evidence against Pelletier and his co-conspirators.

[30] On February 21, 1922, the Massachusetts Supreme Judicial Court found Pelletier guilty of 10 of the 21 charges against him and removed him from office.

Chief Justice Arthur P. Rugg wrote in the court's opinion that Pelletier had "prostituted" his office and used the processes of law "as instruments of oppression in an attempt to wrest money from the blameless and aged" by repeatedly using his position to aid in blackmail and extortion.

The court described their relationship as "conspirators to exert the power of the district attorney to extort money, to terrorize people into surrendering causes of action and otherwise to abuse that office".