Madison - As the deeply divided state Supreme Court wrestled over whether to force one member off criminal cases last year, Justice David Prosser exploded at Chief Justice Shirley Abrahamson behind closed doors, calling her a "bitch" and threatening to "destroy" her.

The incident, revealed in interviews as well as e-mails between justices, shows fractures on the court run even deeper than what has been revealed in public sniping in recent years. Problems got so bad that justices on both sides described the court as dysfunctional, and Prosser and others suggested bringing in a third party for help, e-mails show.

Prosser acknowledged the incident recently and said he thought it was becoming public now in an attempt to hurt him politically. Prosser faces Assistant Attorney General JoAnne Kloppenburg in the April 5 election.

He said the outburst came after Abrahamson took steps to undermine him politically and to embarrass him and other court conservatives.

"In the context of this, I said, 'You are a total bitch,' " Prosser said.

"I probably overreacted, but I think it was entirely warranted. . . . They (Abrahamson and Justice Ann Walsh Bradley) are masters at deliberately goading people into perhaps incautious statements. This is bullying and abuse of very, very long standing."

The Feb. 10, 2010, incident occurred as the court privately discussed a request to remove Justice Michael Gableman from a criminal case.

"In a fit of temper, you were screaming at the chief; calling her a 'bitch,' threatening her with '. . . I will destroy you'; and describing the means of destruction as a war against her 'and it won't be a ground war,' " Bradley wrote in a Feb. 18, 2010, e-mail to Prosser and others.

"In my view, a necessary step to address the dysfunction is to end these abusive temper tantrums. No one brought in from the outside is going to cure this aspect of the dysfunction."

Three days later, Justice Patience Roggensack wrote to Bradley, criticizing her for copying judicial assistants on her e-mail.

"You were trying to make David look bad in the eyes of others, as a person who uses language that we all find offensive - and I include David in that 'we,' " Roggensack wrote. "Do you think that copying others on your e-mail increased the collegiality of the court or decreased it?

"You are a very active participant in the dysfunctional way we carry-on. (As am I.) You often goad other justices by pushing and pushing in conference in a way that is simply rude and completely nonproductive. That is what happened when David lost his cool. He is not a man who attacks others without provocation. Until you realize that you are an active part of the provocation, not much will change. Perhaps a third party will help you realize that you are not part of the solution; you are part of the problem."

The next day, Feb. 22, 2010, Bradley wrote Roggensack.

"Regardless of our disagreements, there is no justification for this abusive behavior," Bradley wrote. "Blaming his abusive behavior on others merely enables it."

Abrahamson and Roggensack did not return calls about the incident.

At the time, passions ran high on the court because the justices had to decide an ethics allegation against Gableman, as well as requests by defense attorneys to force him off nine cases because they believed he was biased against criminal defendants.

Gableman remained on the cases after the justices split 3-3 on the issue. Months later, they split along the same lines on his ethics case.

Abrahamson, Bradley and Justice N. Patrick Crooks voted to find that Gableman violated the judicial ethics code by misstating facts in a campaign ad; Prosser, Roggensack and Justice Annette Ziegler voted to find that he did not violate the ethics code. With no agreement, the case was then abandoned.

Bradley allowed the Journal Sentinel to review the e-mails at the newspaper's request. She blacked out the name of a case mentioned in the e-mails.

She said Prosser's outbursts have occurred on and off over the years, but there has not been one of similar magnitude since the incident described in the e-mails.

Prosser said he'd helped Abrahamson and Bradley in past campaigns but believed they were trying to get him off the court in the upcoming election. Bradley said she had not talked to Kloppenburg about her campaign, but did discuss the "pros and cons and realities" of a court campaign with others, including Marla Stephens.

Stephens, the appellate director for the state Public Defender's Office, ran for the court but did not advance past last month's primary.

Said Prosser: "There is not the slightest doubt that Ann wrote that e-mail to hurt me in this campaign - and here it is surfacing three weeks before the campaign."

Bradley denied that. "I never intended that this would be public," she said. "I just wanted it to stop."

She said she agreed to an interview in part because Prosser had been portrayed as even-keeled during the campaign.

"You can say a lot of good things about David Prosser - and I do, and he is a good man - but you cannot accurately say he has a steady, even temperament," she said.

Kloppenburg has used the divisions on the court as an issue in her campaign against Prosser.

"People in Wisconsin want the Supreme Court to focus on the important work we elect justices to do," Kloppenburg said in an e-mail. "Politics, personality and partisanship that distract from that work are counterproductive and clearly show why the Supreme Court needs new blood."

Asked what he meant when he said he would destroy the chief, Prosser said he meant that he would "tell the truth" publicly about her. Indeed, criticisms of Abrahamson have become prominent in Prosser's campaign.

In an interview last month with Journal Sentinel editors and writers, Prosser portrayed a court where factions have formed around and against Abrahamson, whom he described as a brilliant legal scholar and shrewd politician who marginalizes conservative justices and draws attention to the court's split.

"Who is it who takes these things public all the time?" Prosser asked. "It's the chief justice. . . . She's done some wonderful things, but the rest of us have nothing to contribute" in her eyes.

As Prosser tells it, this isn't the first time Abrahamson has presided over a divided court, and he wasn't always on the opposite side from her. Shortly after he was appointed to the court in 1998, he said, four other justices proposed what he described as "a plot to depose the chief," form an executive committee to run the court and recruit a candidate to run against Abrahamson the following year.

Prosser said he refused to back the plan, because he found it "grossly inconsistent with the constitution" and because Abrahamson "treated me very well." The quartet - Crooks and former Justices Bill Bablitch, Donald Steinmetz and Jon Wilcox - later publicly criticized Abrahamson as confrontational and dismissive and accused her of exceeding her authority.

After winning re-election, Abrahamson thanked Prosser for his support but stressed she didn't owe him anything, Prosser said.

Prosser said the divisions on the court grew worse after Louis Butler was appointed to the court in 2004. Prosser said Crooks swung over to Abrahamson's faction and joined the chief, Bradley and Butler in forming a majority that "completely changed the direction of the court" and was intolerant of other justices' views.

That majority ended in 2008, when Gableman defeated Butler. Crooks declined to comment.

When Ziegler was elected in 2007, after a race in which she was accused of conflicts of interest, Prosser said Abrahamson tried to deny her a formal investiture ceremony. The chief later relented, but Prosser said Ziegler "was treated differently, as a pariah."

In 2008, the court took the unprecedented step of formally reprimanding Ziegler, ruling she had violated the judicial ethics code as a Washington County Circuit Court judge, by presiding over cases involving a bank where her husband served on the board of directors.

Patrick Marley reported from Madison and Larry Sandler reported from Milwaukee.