| William D. Keller | |
| Office: | Senior Judge of the United States District Court for the Central District of California |
| Term Start: | October 29, 1999 |
| Office1: | Judge of the United States District Court for the Central District of California |
| Term Start1: | October 4, 1984 |
| Term End1: | October 29, 1999 |
| Appointer1: | Ronald Reagan |
| Predecessor1: | Seat established by 98 Stat. 333 |
| Successor1: | R. Gary Klausner |
| Office2: | United States Attorney for the Central District of California |
| Term Start2: | 1972 |
| Term End2: | 1977 |
| Appointer2: | Richard Nixon |
| Predecessor2: | Robert L. Meyer[1] |
| Successor2: | Robert L. Brosio (acting) |
| Birth Name: | William Duffy Keller |
| Birth Date: | 29 October 1934 |
| Birth Place: | Los Angeles, California, U.S. |
| Education: | University of California, Berkeley (BS) UCLA School of Law (LLB) |
William Duffy Keller (born October 29, 1934) is a senior United States district judge of the United States District Court for the Central District of California.
Born in Los Angeles, California,[2] Keller received a Bachelor of Science degree from the University of California, Berkeley in 1956 and a Bachelor of Laws from the UCLA School of Law in 1960. He was an Assistant United States Attorney of the Southern District of California from 1961 to 1964. He was in private practice in California from 1964 to 1972. He was the United States Attorney for the Central District of California from 1972 to 1977. He was in private practice in California from 1977 to 1984.
Keller was nominated by President Ronald Reagan on September 11, 1984, to the United States District Court for the Central District of California, to a new seat created by 98 Stat. 333. He was confirmed by the United States Senate on October 3, 1984, and received his commission on October 4, 1984. He assumed senior status on October 29, 1999.