Harsh state judicial campaigns financed by ever larger amounts of special interest money are eating away at public faith in judicial impartiality. There are few places where the spectacle is more shameful than Wisconsin, where over-the-top campaigning, self-interested rulings, and a complete breakdown of courthouse collegiality and ethics is destroying trust in its Supreme Court.

On Monday, a special prosecutor was named to investigate an altercation between two justices on opposite sides of the court’s bitter ideological divide. Ann Walsh Bradley, a member of the court’s liberal wing, has charged that David Prosser, a conservative, put her in a chokehold during a heated exchange shortly before the court upheld the new state law eliminating most collective-bargaining rights for public employees.

Justice Prosser has disputed Justice Bradley’s version of what occurred, and the facts remain unclear. What is certain is that Justice Prosser should have recused himself from that ruling. His vote to uphold the law occurred shortly after his re-election campaign in which he benefited from heavy anti-union independent spending.

Justice Prosser won the April election by a very small margin, prompting a recount. The Milwaukee Journal Sentinel reported that he then raised more than $270,000 for the recount, much of it in $50,000 chunks. (The contribution limits that apply under Wisconsin’s public financing system for judicial races do not extend to recounts.) Some $75,000 of the haul was used to pay fees to a law firm led by an attorney representing conservative groups in a case challenging state campaign disclosure rules, which is scheduled to be heard by the court next month.