Baca was elected Los Angeles County's 30th sheriff against his mentor Sherman Block, who had died in office days prior to the election but remained on the ballot. He was sworn in on December 7, 1998. He was re-elected to a fourth term in 2010. He was criticized for proposing a half-percent sales tax increase in 2004 to hire more deputy sheriffs, placing friends on the payroll, taking of gifts, and for releasing inmates from the Los Angeles County Jail. On May 12, 2017, Baca was sentenced to three years in federal prison for his role in a scheme to obstruct an FBI investigation of abuses in county jails. Baca reported to prison and began his sentence on February 5, 2020.