The FBI launched an investigation into civil rights abuses and corruption inside the Los Angeles County jails in 2010.
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The false statement Baca made was to FBI agents and U.S. attorneys in April 2013. During a voluntary interview as a part of the corruption investigation, Baca said he was not aware of sheriff's officials confronting and threatening to arrest an FBI agent at her home in 2011.
In the plea agreement he reached with the FBI, Baca admitted that he knew his statement was untrue and that it was illegal to lie to federal investigators.
"Today's charge and plea agreement demonstrate that illegal behavior within the Sheriff's Department went to the very top of the organization," U.S. Attorney Eileen M. Decker said. "More importantly, this case illustrates that leaders who foster and then try to hide a corrupt culture will be held accountable."
Former federal prosecutor responds to Lee Baca guilty plea
As part of the plea deal, Baca faces a sentence of up to six months in federal prison, but the actual sentence will be determined by the federal judge presiding over the case.
If the court decides to impose a greater sentence, Baca can withdraw his plea agreement and would face a possible indictment.
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In September 2015, Baca wasn't granted immunity in an upcoming corruption trial of his former LASD Undersheriff Paul Tanaka.
Prosecutors allege that Tanaka oversaw a secret plan in 2011 to hide inmate-turned FBI informant Anthony Brown from FBI handlers. Brown was booked and re-booked under a series of false names, moved to multiple locations and eventually told by sheriff's officials that the FBI abandoned him.
Seven former LASD deputies, sergeants and lieutenants were convicted in 2014 for their roles in the operations.
Baca hired his own criminal defense attorney should he be called to the stand in Tanaka's trial, which is scheduled for March 22.