SANTA ANA ( — The Justice Department has opened an investigation into a long-running scandal over the use of jailhouse informants in Orange County.

The civil pattern-or-practice investigation will look into allegations that county prosecutors and sheriff’s officials used jailhouse snitches to get information from defendants in violation of their constitutional rights, the U.S. attorney’s office in Los Angeles said in a statement Thursday.

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The probe will also examine allegations that prosecutors in the Southern California county failed to turn over required evidence to defense attorneys.

“A systematic failure to protect the right to counsel and to a fair trial makes criminal proceedings fundamentally unfair and diminishes the public’s faith in the integrity of the justice system,” Principal Deputy Assistant Attorney General Vanita Gupta said in the statement.

“Our investigation will examine the facts and evidence to determine whether the District Attorney’s Office and Sheriff’s Department engaged in a pattern or practice of violating these rights,” Gupta said.

The Justice Department said Orange County District Attorney Tony Rackauckas requested the review. Last year, Rackauckas formed a committee to review the use of jailhouse informants.

The scandal began several years ago after the defense lawyer for mass killer Scott Dekraai learned that a jailhouse informant had been chatting up his client even though he already had a lawyer, an alleged a violation of his client’s constitutional rights.

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The discovery prompted the judge to open hearings into the issue and eventually yank county prosecutors from the case — a decision that was upheld by a state appeals court last month.

Since the discovery, other criminal cases in the county where jailhouse snitches were used have also been affected.

The Orange County Sheriff’s Department and Orange County District Attorney’s Office released statements Thursday saying they welcome the investigation:

“The OCDA believes at the conclusion of USDOJ Civil Rights Division’s review, they will conclude that the OCDA did not engage in systematic or intentional violation of civil rights of any inmate and not innocent person was wrongfully convicted,” Rackauckas said in a statement.

“It is, and has been, our ultimate goal to have a jail system that is exemplary and that upholds its duty to the inmates, our staff and the people of Orange County,” Orange County Sheriff Sandra Hutchens said.

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