Baca told top officials in county government late Monday that he believes stepping down will help the department recover after several years of tumult and criticism, according to sources familiar with the conversations.
Baca's decision comes a month after federal prosecutors filed criminal charges against 18 current and former sheriff's deputies accused of beating jail inmates and visitors, trying to obstruct the FBI and other crimes following an investigation of corruption inside the nation's largest jail system.
Baca won office in 1998 after his rival, incumbent Sheriff Sherman Block, died days before the election. In the next three elections, Baca easily won in primaries against fields of lesser-known candidates, avoiding head-to-head runoff elections. By 2010, no one bothered to challenge him.
Recently, Baca, 71, was coping not just with the FBI probe but searing criticism of his leadership from a blue-ribbon commission appointed by the Board of Supervisors to examine allegations of jail abuses.
Last year, the U.S. Department of Justice accused sheriff's deputies of engaging in widespread unlawful searches of homes, improper detentions and unreasonable force as Antelope Valley authorities conducted a systematic effort to discriminate against African Americans who received low-income subsidized housing.