Clarence Charles Newcomer (January 18, 1923 – August 22, 2005) was a United States federal judge.
Born in Mount Joy, Pennsylvania, Newcomer was a U.S. Naval Reserve Lieutenant during World War II, from 1943 to 1946, and then received an A.B. from Franklin and Marshall College in 1944 and a J.D. from Dickinson School of Law in 1948. He was in private practice in Lancaster, Pennsylvania from 1950 to 1971. He was a Special deputy commonwealth attorney general of Pennsylvania from 1953 to 1954. He was an Assistant district attorney of Lancaster County, Pennsylvania from 1960 to 1968. He was a District attorney of Lancaster County, Pennsylvania from 1968 to 1972.
Newcomer was a federal judge on the United States District Court for the Eastern District of Pennsylvania. Newcomer was nominated by President Richard Nixon on November 17, 1971, to a seat vacated by C. William Kraft, Jr.. He was confirmed by the United States Senate on November 23, 1971, and received his commission on November 30, 1971. He assumed senior status on January 19, 1988. Newcomer served in that capacity until August 22, 2005, due to his death.
He died in Stone Harbor, New Jersey.