"I will go out on my terms," Baca said. "I don't see myself as the future. I see myself as part of the past."
The 71-year-old Baca was emotional as he talked about the importance of the sheriff's department and the people they serve.
"I've been proud and honored to serve the Los Angeles County Sheriff's Department and the people of this greatest of counties, Los Angeles County, for the past 48 years," he said.
Baca said there are many reasons why he is retiring after serving four terms, but he noted that the "prevailing one is the negative perception this upcoming campaign has brought to the exemplary service provided by the men and women of the sheriff's department."
Baca has been facing criticism following an FBI investigation into corruption and abuse at county jails. Eighteen deputies were arrested last month and face federal charges for inmate beatings.
The federal investigation described a culture of violence at Men's Central Jail and Twin Towers Correctional Facility. Baca admitted the department made mistakes in hiring deputies who had questionable backgrounds, but he has insisted that the abuse allegations do not reflect on the department as a whole.
"Eighteen people out of 18,000 does not constitute a department," Baca said.
The news caught many people off guard, including those close to the sheriff.
"It was fully unanticipated, and therefore, I think it's fair to say that I'm quite surprised by it," said L.A. County Supervisor Mark Ridley-Thomas. "Everything that had been indicated up to this point was that he was fully engaged in a re-election scenario."
Baca's term would have expired in the summer, but because he is stepping down early, Baca said he will be recommending that Terri McDonald be named the interim sheriff. McDonald is a 24-year veteran of the California Department of Corrections and Rehabilitation who was recently named assistant sheriff.