OAKLAND (CBS SF) — A former Contra Costa County sheriff’s deputy is due to appear before a federal judge in Oakland Feb. 7 for the setting of the next dates in his prosecution on charges of so-called “dirty DUI” arrests.

Stephen Tanabe, 48, of Alamo, was indicted by a federal grand jury last week on four charges accusing him of aiding former private investigator Christopher Butler in arranging the drunken driving arrests of three husbands in divorce cases.

He pleaded not guilty to the charges before U.S. Magistrate Laurel Beeler on Monday.

Beeler granted him bail of $400,000 and ordered him to return to the court of U.S. District Judge Saundra Armstrong Feb. 7 for the setting of future dates, including a possible trial date.

The four charges in the Dec. 15 indictment are one count of conspiring to extort under color of official right, or under his position as an officer, and three counts of extortion under color of official right.

The indictment alleges that Butler gave Tanabe cocaine and a firearm in exchange for his help in making the arrests of three husbands or ex-husbands of women who were clients of Butler and were in the midst of divorce or child custody disputes.

Butler allegedly arranged for an undercover employee to make plans to meet each victim at a bar.

Butler would then “direct the employee to entice the target to drink alcohol until he was intoxicated, and have a police officer waiting outside the bar to stop and arrest the target for drinking under the influence,” the indictment alleges.

Tanabe allegedly personally made two of the arrests on Jan. 9 and 14 of this year.

In a third case in Nov. 2, 2010, he allegedly arranged for another deputy sheriff to wait outside the bar and make the arrest while Tanabe remained inside the bar “monitoring the alcohol intake of the target,” according to the indictment.

Tanabe’s defense attorney, Tim Pori, was not available for comment Tuesday.

The prosecution grew out of a Contra Costa County law enforcement scandal that began with an investigation of stolen drug evidence and expanded to a probe of alleged drug sales, theft, bribery, possession of illegal weapons and prostitution.

Butler, former Central Contra Costa County Narcotics Enforcement Team (CNET) commander Norman Wielsch and former San Ramon police officer Louis Lombardi have previously been charged in federal court.

They and Tanabe also face state court charges filed by the Contra Costa County District Attorney’s Office and are scheduled to have a preliminary hearing in that case on March 5.

Butler and Wielsch were federally indicted in August on charges of selling methamphetamine and marijuana, stealing from a federally funded program and extorting payments from employees running an illegal massage parlor that Butler and Wielsch allegedly established.

They are due to appear before Armstrong in Oakland on Jan. 24.

Lombardi, who was assigned to work with CNET between 2005 and 2009, was charged in a criminal complaint filed in May and revised in October with possessing a stolen gun, selling marijuana and methamphetamine and depriving unnamed victims of their civil rights.

He previously pleaded not guilty but is scheduled to enter a change of plea before Armstrong on Jan. 26.

Butler is identified only by his initials in Tanabe’s indictment, but was identified by name in an affidavit filed in the state court case by Contra Costa County Sheriff’s Detective Sgt. Jason Vorhauer in March.

That affidavit alleged that two deputies told investigators they aided Butler and Tanabe in the Jan. 14 and November 2010 “dirty DUI” arrests.

The alleged victim in the Jan. 14 arrest was identified as Mitchell Katz, owner of the Mitchell Katz Winery in Pleasanton, when Katz filed a federal civil rights lawsuit on Dec. 1 against Contra Costa County; his estranged wife, Alicia Spenger; Tanabe; Butler and others.

Katz, a Livermore resident, contends in the lawsuit that he was lured to a Danville bar on Jan. 14 by Carl Marino, a Butler employee who was posing as the producer of a television reality show.

The lawsuit alleges that Katz was surrounded at the bar by four other women who claimed they were familiar with his winery but were also allegedly employed by Butler.

Katz was pulled over and arrested by Tanabe when he left the bar.

Katz says in the lawsuit that he was later told by Marino in an e-mail in March that the operation was a “set up” and that Marino had told the U.S. Department of Justice about the alleged scheme.

Also in March, county prosecutors declined to file any DUI charges against Katz, telling Katz’s defense lawyer in a letter that the arrest was illegal because Katz “”appeared to be the victim of an intentional conspiracy to entrap targeted victims of Tanabe’s accomplice, Christopher Butler.”

The lawsuit is pending in federal court in Oakland.

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