Reed Saxon / AP Los Angeles County Men's Central Jail, operated by the Los Angeles County Sheriff, on Oct. 3, 2012.

Nearly 20 current and former Los Angeles County sheriff’s deputies were expected to be arrested Monday in connection with a two-year federal probe into corruption and inmate abuse in the county jail system.

Sixteen deputies, most still active in the department, were either arrested without incident or surrendered Monday to agents with the Federal Bureau of Investigation, according to law enforcement sources familiar with the investigation. Two others had not yet been arrested by Monday afternoon. None of those arrested ranked higher than lieutenant.

Four grand jury indictments and one criminal complaint allege the unjustified beating of inmates, unjustified detention and a conspiracy to obstruct a federal investigation.

“The five cases allege a wide scope of illegal conduct,” said André Birotte Jr., U.S. Attorney for the Central District of California. “This investigation started by focusing on misconduct in county jails, and we uncovered examples of civil rights violations that included excessive force and unlawful arrests.”

“Our investigation also found that these incidents did not take place in a vacuum – in fact, they demonstrated behavior that had become institutionalized. The pattern of activity alleged in the obstruction of justice case shows how some members of the Sheriff’s Department considered themselves to be above the law.”

The arrests seem to culminate an investigation that included allegations that deputies tried to hide an informant who was providing information to the FBI while locked up after the deputies discovered the informant had a cell phone.

Seven current and former members of the LASD were accused in an indictment that alleges a conspiracy to obstruct justice, after the deputies learned that an FBI informant was being held in the Men’s Central Jail. The deputies learned that the informant had received a cell phone from a deputy who allegedly received a bribe, and that the informant was assisting the FBI in investigating alleged corruption and civil rights violations.

The defendants then allegedly attempted to hide the informant from the FBI and the U.S. Marshals Service. Prosecutors say they altered records to make it look like the informant had been released from custody, and then rebooked him under a different name and told him he had been abandoned by federal law enforcement. Two sergeants named in the case allegedly confronted an FBI agent at her home in order to intimidate her into divulging details of the investigation.

Lieutenant Gregory Thompson, charged in the indictment, no longer works for the Sheriff’s Department. The other deputies named are Gerard Smith, Mickey Manzo, James Sexton, Scott Craig and Maricella Long.

In an interview with the Los Angeles Times, the informant said he had been using his phone to take photos and document excessive force inside Men's Central Jail. Anthony Brown told the paper that FBI agents regularly visited him in court and at the jail, where he supplied them with the names of allegedly corrupt and abusive deputies.

In another indictment, a sergeant and four deputies are charged with arresting or detaining five individuals, including the Austrian consul general, who was handcuffed, when they visited inmates at the Men’s Central Jail in 2010 and 2011. Lead defendant Eric Gonzalez no longer works for the department. The four deputies, Sussie Ayala, Fernando Luviano, Pantamitr Sunggeemoge and Noel Womack, are charged with participating in at least one of four incidents in which victims allegedly suffered civil rights violations. One incident left a victim permanently disabled after he suffered a broken arm and dislocated shoulder.

Two deputies are charged in a six-count indictment with making false statements and civil right violations. Bryan Brunsting is charged in relation to an incident in which an inmate was allegedly assaulted and injured. Broth Brunsting and Jason Branum are charged in another assault. The indictment alleges that Brunsting then used deputies he was training to file reports covering up the abuse.

Deputy Richard Piquette is charged in the fourth indictment with illegal building and possessing an assault rifle. The investigation is being handled by the ATF.

Another of the cases involves three LASD deputies who are brothers who allegedly used a “buy-and-bail” mortgage fraud scheme to help buy a home in Corona, Calif. Billy, Benny and Johnny Khounthavong allegedly made false statements to buy the home and then made more false statements to walk away from the property when the value of the home fell below what they owed on it. The brothers allegedly avoided more than $340,000 in mortgage debt via the scheme.

Sheriff Lee Baca called the arrests "a sad day for the Los Angeles County Sheriff's Department."

"We do not tolerate misconduct by any deputies," said Baca. "This department is grounded in its core values, namely to honorably perform our duties with respect for the dignity of all people, and integrity to do right and fight wrongs. We have cooperated fully with the federal investigation and will continue to do so."

The arrests and jail abuse allegations represent the latest series of controversies to roil the administration of Sheriff Baca, who is seeking a fifth four-year term in next November’s elections. One of his chief rivals is Paul Tanaka, a former undersheriff and Baca confidant who retired from the department earlier this year amid a bitter falling out.

In June, the U.S. Justice Department found that deputies patrolling the Antelope Valley in northern Los Angeles County repeatedly harassed and intimidated Blacks and Latinos including using racial profiling and excessive force.

In 2012, a Sheriff’s captain at the Carson station was placed on administrative leave after the department alleged she was giving information to a suspected narcotics dealer.

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