LOS ANGELES (CBSLA.com) — Former Los Angeles County Sheriff Lee Baca was indicted Friday on charges of conspiring to obstruct justice, obstructing justice and lying to the federal government less than a week after he withdrew from a plea agreement with federal prosecutors.

If convicted of all charges, Baca, 74, could face up to 20 years in federal prison, according to the U.S. Attorney’s Office.

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On Monday, Baca, who is suffering from Alzheimer’s disease, backed out of a plea deal he reached with prosecutors earlier this year that called for him to serve no more than six months behind bars on a single count of lying to the FBI.

U.S. District Judge Percy Anderson balked at the plea agreement, saying the sentence was too lenient considering the retired lawman’s role in obstructing an FBI investigation into Los Angeles County jails.

Baca said he would go to trial to “set the record straight” before his illness advances.

Baca’s attorney, Michael Sweiback, has said “We have a very, very small window of time that we believe Mr. Baca’s life will be normal. If there was a possibility that he was going to go beyond his good years in prison, then he should go out and fight.”

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In the plea agreement that has been withdrawn, Baca acknowledged that he lied to investigators and knew about attempts to hinder the FBI investigation into corruption and beatings at the nation’s largest jail system.

Baca stepped down in January 2014 after leading the Los Angeles County Sheriff’s Department for 16 years.

Former Undersheriff Paul Tanaka was convicted and sentenced to five years for conspiracy and obstruction of justice.

Twenty members of the Sheriff’s Department have been convicted in the case that began after deputies discovered an FBI agent was posing as an inmate to gather evidence about civil rights abuses and corruption at jails.

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