Two agencies announced Monday that they are conducting separate ethical and criminal investigations into an alleged physical altercation between two Wisconsin Supreme Court justices.As first reported Saturday by the Wisconsin Center for Investigative Journalism and Wisconsin Public Radio, Justice David Prosser allegedly grabbed fellow justice Ann Walsh Bradley by the neck with both hands in her chambers, in the presence of other justices. Prosser initially declined to discuss the allegations but later told the Milwaukee Journal Sentinel they would be “proven false.”

The Wisconsin Judicial Commission, which investigates allegations of misconduct by the state’s judges and justices, confirmed in a statement Monday that it had “received information concerning an incident that occurred at the Wisconsin Supreme Court” and “authorized an investigation of the incident at its meeting on Friday, June 24, 2011.”

“The investigation will be conducted without prejudgment in a fair and thorough manner in accord with Commission procedures,” the Judicial Commission statement said. “The Commission will have no further comment.”

Meanwhile, the Dane County Sheriff’s Office has accepted a request from state Capitol Police Chief Charles Tubbs to conduct a criminal investigation into the matter.

Tubbs’ statement was sparse: “After consulting with members of the Wisconsin Supreme Court, I have turned over the investigation into an alleged incident in the court’s offices on June 13, 2011 to Dane County Sheriff Dave Mahoney. Sheriff Mahoney has agreed to investigate this incident and all inquiries about the status of the investigation should be made with the Sheriff’s Department.”

Tubbs, in comments to reporters, would not say why his office decided against investigating the matter on its own authority, saying this was a question for the Dane County Sheriff’s Office.

Mahoney told the Center that Tubbs asked his office to handle the matter “to avoid any potential conflict of interest.” The conflict, Mahoney explained, is between the Capitol police’s responsibility to provide for the safety and security of the Supreme Court and its need to ask the “pointed questions” inherent in “investigating alleged criminal conduct on the part of a Supreme Court justice.”

Knowledgeable sources, who spoke on condition that they not be named in order to maintain professional relationships, have said the incident was reported to Tubbs shortly after it occurred. Tubbs’ statement is the first official confirmation that the incident took place on June 13, the day before the court released is decision upholding a bill to strip public employees in Wisconsin of most of their collective bargaining rights. The argument that precipitated the altercation was over the timing of the release of that decision.

The Sheriff’s Office, in its statement, said it was opening an investigation into the incident, adding that it “recognizes the significance and sensitive nature of this investigation. Beginning today, detectives will work diligently to conduct a thorough and timely investigation. Because this case is in the very early stages, no further information is available at this time.”

The Capitol police are a division of the state Department of Administration, part of the administration of Gov. Scott Walker. Calls to DOA spokesperson Carla Vigue from the Center and WPR were not promptly returned.

Dane County District Attorney Ismael Ozanne told the Center that his office has had no involvement in the case thus far but would likely be the agency to whom the matter is referred after the Sheriff’s Office completes its investigation. At that point, “we would look at it,” initially to determine if there was “a conflict or an appearance of conflict” in having the Dane County DA’s Office handle the case.

Ozanne is a named party to the decision, Ozanne v. Fitzgerald, over which the argument between Prosser and Bradley ensued.

If Ozanne does take the case, he would review the recommendations of the Sheriff’s Office and decide what if any charges are appropriate. If there is a perceived conflict, a special prosecutor could be appointed or the case could be handled by another district attorney’s office.

Jim Alexander, the Judicial Commission’s executive director, told Wisconsin Public Radio that a complaint does not have to be filed before an investigation can be launched. He said he cannot say in this case whether a complaint had been filed, citing confidentiality rules, but added that if the justices or complainant would waive the confidentiality requirement, he could then reveal the complaint and who registered it.

Calls to both Prosser and Bradley were not returned.

But late Monday, Prosser issued a statement pledging his “full cooperation” with the investigations, saying he “believes a thorough and impartial review will be the proper channel for the facts surrounding this incident to be reported to the general public.”

In a statement issued late Saturday, Prosser denied the allegations, saying: “Once there’s a proper review of this matter and the facts surrounding it are made clear, the anonymous claim made to the media will be proven false. Until then, I will refrain from further public comment.” The Milwaukee Journal Sentinel quoted unnamed sources who said that Prosser’s conduct with Bradley’s neck was incidental, as he raised his arms in defense as she charged toward him with her fists in the air.

A few hours later, Bradley went public with her allegations, telling the Journal Sentinel, “The facts are that I was demanding that he get out of my office and he put his hands around my neck in anger in a chokehold.” She dismissed the alternative version that has her as the aggressor: “You can try and spin those facts and try to make it sound like I ran up to him and threw my neck into his hands, but that’s only spin.”

Gov. Scott Walker commented on the allegations Monday morning in an interview with Wisconsin Public Radio: “Even if the truth is somewhere in-between there, no matter which part of that story is accurate, [what] it would suggest overall is that there are some real troubles that I think are very serious in terms of the relationship and conduct of the Supreme Court, and that certainly has to be resolved. In a free society, there’s got to be confidence in the judiciary, and certainly the fact that there’s that kind of tension there I don’t think is healthy for anybody.”