DES MOINES - Even though the 2010 election is still a year away, GOP gubernatorial candidate Rod Roberts already knows how he plans to vote.

Roberts, a five-term state representative, said Wednesday he will oppose three members of the Iowa Supreme Court who ruled in favor of legalizing same-sex marriage in Iowa when they come up for a retention vote on next year's general election ballot.

The Carroll Republican said he intended to vote to remove Chief Justice Marsha Ternus of Des Moines and Justices Michael Streit of Johnston and David Baker of Cedar Rapids - three members of the court who joined in issuing the unanimous decision in April overturning Iowa's 1998 law defining marriage as only between one man and one woman.

"We need to send a message to the Iowa Supreme Court that they are accountable to the people of Iowa," Roberts said in a statement. "The problem with judicial activism is that it thwarts the will of the legislature and of the people of Iowa. Next November, it is our duty as voters to let these justices know what we think of their judicial activism."

Get news headlines sent daily to your inbox

However, members of the Iowa Bar Association warned that Iowa's tradition of maintaining an independent judiciary insulated from politics could be hurt if justices were removed for interpreting the law in a fair and impartial manner that did not jibe with someone's partisan view.

"That would be worrisome," said Des Moines attorney Dwight James, who serves on the bar association's independence of the judiciary committee.