MADISON, Wis. -- Wisconsin Supreme Court Justice David Prosser grabbed fellow Justice Ann Walsh Bradley around the neck in an argument in her chambers last week, according to three sources cited in in a story written by the Wisconsin Center for Investigative Journalism and Wisconsin Public Radio.

The report cites unnamed sources that said an argument occurred before the court’s release of a decision last week upholding the publication of a bill that cut nearly all collective bargaining rights of most public employees.

During the alleged argument, a physical altercation between Prosser and Bradley occurred in the presence of other justices, the report said.

The report said that Bradley asked Prosser to leave her office and that was when Prosser grabbed Bradley by the neck with both hands.

Both justices declined comment to the reporters covering the story, but the sources said that Capitol Police Chief Charles Tubbs was notified of the incident, according to the report.

One source said Tubbs came in to meet with the entire Supreme Court about this matter, according to the report. Tubbs was contacted by Wisconsin Public Radio, but declined to comment, the report said.

The Wisconsin Judicial Commission, a body that investigates allegations of misconduct involving judges, was also made aware of the incident, a source said.

The incident was investigated jointly by reporters Bill Lueders and Kate Golden, of the Wisconsin Center for Investigative Journalism, and Wisconsin Public Radio reporters Gil Halsted and Teresa Shipley.

The state Supreme Court voted 4-3 to overturn Dane County Judge Maryann Sumi's ruling that the bill didn't follow the state's open meeting laws. The court's decision cleared the way for the law to take effect.

Prosser, a former Republican lawmaker in Wisconsin, who was appointed to the Wisconsin Supreme Court in 1998 by then Gov. Tommy Thompson, narrowly won reelection in April over JoAnne Kloppenburg, but not before a statewide recount was finished.

The Associated Press contributed to this story.