Public universities and local governments can't provide health insurance to the partners of gay employees without violating the state constitution, the Michigan Court of Appeals ruled Friday.

A three-judge panel said a 2004 voter-approved ban on gay marriage also applies to same-sex domestic partner benefits.

"The marriage amendment's plain language prohibits public employers from recognizing same-sex unions for any purpose," the court wrote.

The decision reverses a 2005 ruling from a county judge who said universities and government agencies could provide the benefits.

A constitutional amendment passed by Michigan voters in November 2004 made the union between a man and a woman the only agreement recognized as a marriage "or similar union for any purpose." Those six words led to the court fight over benefits for gay couples.