LOS ANGELES (CBSLA.com) — A former Los Angeles County sheriff’s deputy was expected to testify Tuesday in the first part of a federal corruption trial of former longtime Sheriff Lee Baca.

Gilbert Michel, 43, is at the center of the jail scandal that shook up the department and led to the conviction of over a dozen officials. Michel was the first to be charged in a wide-ranging FBI investigation into misconduct and corruption in the jails after he was caught in a sting operation in August 2011 smuggling a cell phone to an inmate in return for a $1,500 bribe.

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Baca suddenly retired in 2014 at the height of the federal probe. He is now being tried on conspiracy and obstruction counts in connection with the case. He is accused of trying to disrupt the FBI investigation.

Baca is also facing a second trial — on a charge of making false statements to federal authorities — following the conclusion of these proceedings now in their second week in downtown Los Angeles.

Baca — who ran the nation’s largest sheriff’s department for 16 years beginning in 1998– is in the early stages of Alzheimer’s disease. U.S. District Judge Percy Anderson split the trial into two parts after he agreed to allow testimony by an expert on dementia — but only as it relates to the lying charge.

The 2011 discovery of the cell phone by sheriff’s officials exposed the FBI’s secret investigation inside the jail and disrupted the bureau’s plans to carry out a larger probe of corruption inside the Sheriff’s Department.

The discovery of the phone hidden within a jail informant’s bag of Doritos also set into motion a secret program known by participants as Operation Pandora’s Box, a conspiracy by sheriff’s officials to thwart the FBI probe. As a result, 10 sheriff’s officials were convicted of obstruction of justice or other charges.

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Michel was sentenced to six months behind bars in June after pleading guilty to the bribery charge and agreeing to testify against other sheriff’s officials in subsequent trials, including the current case against Baca.

Last week, two ex-deputies who were convicted of obstructing the FBI jails investigation told the jury that they believed they were following orders from Baca when they worked to derail the federal probe by hiding the informant within the jail system.

Former deputies James Sexton and Mickey Manzo testified about the steps they took to conceal the whereabouts of Anthony Brown, who was working as a federal informant.

Both ex-lawmen said that they believed their orders came from Baca and then-Undersheriff Paul Tanaka.

Tanaka, who alleges that Baca initiated the plan, was sentenced to five years in prison after his April conviction on conspiracy and obstruction charges.

Prosecutors allege that Baca put into motion the scheme — overseen by Tanaka — to derail the investigation by intimidating the lead agent in the case, pressuring deputies not to cooperate and keeping Brown hidden.

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