CHICAGO (CBS) — Already in prison for the murder of his third wife, former Bolingbrook cop Drew Peterson on Tuesday pleaded not guilty to charges he tried to hire a hitman to kill the prosecutor who put him behind bars.

Last month, the Illinois Attorney General’s office and Randolph County prosecutors announced Peterson had been charged with one count of solicitation of murder for hire, and one count of solicitation of murder, for allegedly trying to put a hit on Will County State’s Attorney James Glasgow.

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The prosecution revealed Tuesday that authorities twice used court-ordered wiretaps to eavesdrop on Peterson in prison — from Oct. 24 to Nov 23, 2014; and from Nov. 23 to Dec. 22, 2014.

Peterson appeared in court in downstate Chester on Tuesday morning, his feet in shackles, and pleaded not guilty. He also waived a preliminary hearing on the charges, and asked for a trial as soon as possible.

Peterson’s defense attorney said they did not want to divulge further details of the case in court, because they don’t want to expose the identity of the person who wore a wire for the government.

Jury selection was tentatively scheduled for mid-July, with the trial possibly starting in late July.

After entering the courtroom Tuesday, Peterson mugged for courtroom sketch artists, pointing to his wry smile. He also whispered to reporters, telling them to “check these out” as he donned a pair of prison-issued eyeglasses.

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Prosecutors have said, between September 2013 and December 2014, while in prison, Peterson solicited an unidentified person to find someone he could pay to kill Glasgow, who personally led the prosecution team in Peterson’s 2012 murder trial.

The charges against Peterson, 61, were filed in Randolph County, where he is in prison at Menard Correctional Center, serving a 38-year prison sentence for the murder of his third wife, Kathleen Savio, who drowned in a bathtub in March 2004 while the couple was in the midst of a divorce.

Peterson also has been named a suspect in the disappearance of his fourth wife, Stacy, but she has never been found, and no charges have been filed.

Stacy’s sister, Cassandra Cales, attended Peterson’s court hearing on Tuesday. She said she was “just to show Drew that I’m not going anywhere, and I won’t stop until Stacy’s found.”

She said, the more criminal charges against Drew Peterson, the better.

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“Keep racking him up. I mean, he’s going to die in there anyways, so just keep piling it up,” Cales said.