Advocates of the legislation say it would codify existing practice into law and preemptively protect religious child-placing organizations from repercussions if Michigan ever legalizes gay marriage or civil unions. In 2011, Illinois ended long-standing contracts with Catholic Charities to provide foster care and adoptions because of the group's practice of referring unmarried couples to other agencies.

Critics say the bills would authorize discrimination by agencies receiving state funding for child placements.

It is the latest dispute over "conscience" legislation, measures pushed by the Michigan Catholic Conference and other groups to protect their religious freedom. A bill that would let health workers and businesses object to providing contraception or other medical services on moral grounds has been pending on the floor of the Senate for five months.