FILE - In this July 17, 2012, file photo, Maricopa County Sheriff Joe Arpaio, right, and Maricopa County Sheriff's Cold Case Posse Lead Investigator Mike Zullo speak at a news conference in Phoenix. Zullo refused to answer questions in court on Tuesday, Nov. 10, 2015, about a secret investigation for Sheriff Joe Arpaio that critics say was aimed at discrediting a judge. (AP Photo/Matt York, File)
PHOENIX (AP) – A leader of an Arizona sheriff's office posse refused to answer questions in court on Tuesday about a secret investigation that critics say was aimed at discrediting a judge.
Mike Zullo invoked his Fifth Amendment right against self-incrimination 37 times in refusing to answer questions about his work in investigating the case for Sheriff Joe Arpaio.
"Taking the Fifth, sir," Zullo said, responding to a question about whether Arpaio had asked him to get information on the judge.
Zullo has become a central figure in the contempt-of-court case against Arpaio that has dragged on for more than six months.
As the leader of one of Arpaio's posses, Zullo led the sheriff's 2012 investigation into the authenticity of President Barack Obama's birth certificate and was assigned to a probe that critics say targeted U.S. District Judge Murray Snow. The judge had ordered a sweeping overhaul of Arpaio's office in 2013 after finding his officers had profiled Latinos.
Critics say documents produced in the investigation suggest that the sheriff's office was trying to prove a conspiracy between Snow and the U.S. Justice Department against the sheriff. Snow has characterized the investigation as an attempt to construct a "bogus conspiracy theory" to discredit him.
Arpaio insists he wasn't investigating the judge and maintains his officers examined claims that that someone had taken the bank information of thousands of people.
While Arpaio maintained that Snow's bank account information had been hacked, another investigation has testified he never examined whether the judge's bank information had been breached.
Zullo answered two questions during 15 minutes on the witness stand late Tuesday and invoked the Fifth Amendment on all other questions. He will take the witness stand again Thursday.
The posse leader has explained his decision to take the Fifth by citing a court filing in which Arpaio's opponents say investigators could be implicated in federal crimes — such as intimidation of federal court — for their work on the case. Zullo is a former police officer.
Federal prosecutors declined a request two weeks ago from an Arpaio lawyer to grant Zullo immunity.
Zullo was called to testify at contempt hearings called over Arpaio's disobedience of Snow's orders. The sheriff has acknowledged letting his officers conduct immigration patrols for 18 months after the judge had ordered them stopped.
The hearings could lead to civil fines for the sheriff, more court-ordered changes to the agency and possible criminal contempt hearings for Arpaio.
The six-term sheriff has been accused in the past of investigating judges who were at odds with him — and the county paid legal settlements with judges who were investigated.
But the contempt hearings mark the boldest public attempt to confront Arpaio on the recurring retaliation allegation.
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