The new law includes a section that says no religious organization -- including some hospitals, cemeteries, schools and community centers -- or its employees may be required to treat as valid any civil union, providing a religious exemption "of unparalleled and alarming scope," Chafee said in a statement.

As a result, a civil union spouse could be denied the right to make medical decisions for his or her partner, access to health insurance benefits, property rights in adjoining burial plots or family memberships at some community centers. That could cause partners significant harm at critical moments in their lives, the governor said.