A judge on Washington State's highest court is lashing out at Bill Gates and two other billionaires who have spent at least $850,000 on efforts to oust him from the bench.

Washington State Supreme Court Charles "Charlie" K. Wiggins, elected six years ago, is vying for another term. Opposing his campaign are two political action committees backed with six-figure donations from America's richest man, Bill Gates, fellow Microsoft Inc. co-founder Paul Allen, and money manager Ken Fisher.

One of the PACs — funded by the Microsoft billionaires — is running ads urging voters to back the judge's challenger, municipal court judge Dave Larson. The other, supported by Mr. Fisher, is attacking Justice Wiggins's record, focusing on a child-pornography case in which he voted to overturn the conviction of a man accused of possessing child pornography.

Bill Gates donated $200,000. The company that manages Mr. Allen's business and charitable undertakings gave another $300,000. Mr. Fisher donated $350,000 to the other PAC.

Justice Higgins is none too pleased about it, reports the Seattle Times:

“This is an attack on the credibility of the court,” Wiggins said, expressing astonishment over what he called an “eleventh-hour” stroke of the pen by a group of billionaires.

The independent spending dwarfs the $205,000 raised by Wiggins’ campaign. Groups including Planned Parenthood have reported an additional $12,000 in independent spending to support him.

Justice Wiggins's tenure has been marked by a number of controversial rulings, including a 2015 decision he favored declaring the state's system of funding charter schools unconstitutional and another case where the court ordered the state to spend billions of dollars more on public schools.

Mr. Gates and other donors "were big supporters of the state’s charter-schools law," says the Seattle Times.

A former Eagle Scout and U.S. Army captain from Bainbridge Island, Justice Wiggins worked in private practice for about two decades before joining the judiciary, first as an appellate judge.

His record was defended in a letter from former Washington Supreme Court Chief Justice Gerry Alexander, which was co-signed by three former prosecutors and a retired law professor.

The letter called the child pornography attack ads an irresponsible distortion of the judge's positions:

"The decision was rooted in upholding the constitutional right to privacy under Washington's search and seizure laws," it stated. "To attempt to scare voters into thinking otherwise is grossly unfair—to Justice Wiggins and voters."