Alabama Chief Justice Roy Moore is calling on Congress to impeach Justice Ruth Bader Ginsburg if she does not recuse herself from a Supreme Court case challenging gay marriage bans in four states.

The high court heard arguments in the case in April and is expected to hand down a decision next month.

Earlier this year, Moore ordered Alabama probate judges not to issue marriage licenses to gay and lesbian couples, contradicting a federal judge's ruling striking down the state's ban and creating confusion in the state.

(Related: Federal judge says ruling striking down Alabama's gay marriage ban applies statewide.)

On Friday, he told Family Research Council (FRC) President Tony Perkins that the states should defy the Supreme Court if it strikes down bans nationwide.

“The final say is the United States Constitution,” Moore said. “It is not the words of a justice. … And you find nowhere in there marriage.”

“We have justices on the Supreme Court right now who have actually performed same-sex marriages, Ginsburg and Kagan,” he said. “Congress should do something about this.”

Moore called on Congress to impeach Justice Ginsburg if she does not recuse herself from the case.

It should be noted that the marriages celebrated by Ginsburg and Kagan were legal, performed in states where it was permissible. Oddly, Moore is not calling on justices who have performed heterosexual marriages to step down from the case.

(Related: While presiding 5th same-sex wedding, Ruth Bader Ginsburg emphasizes word “constitution.”)