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Propsition 8 opponent Sister Maudlin Mascara argues with Proposition 8 supporter George Papko outside of the California Supreme Court May 26 in San Francisco.

The movement toward legalizing same-sex marriage in New Hampshire has hit a bump. Gov. John Lynch, a Democrat, said he would sign a same-sex marriage bill only if it included new language expanding protection for religious institutions that might object to same-sex marriage. Last week, the state's House of Representatives rejected that amendment. So for the moment, the matter is stalled in New Hampshire.

But whatever the outcome, Lynch may have moved the debate over same-sex marriage forward, at least by isolating it from the question of how it affects religious groups.

For some time, scholars have debated this issue, and some are now urging states considering same-sex marriage laws to include strong protections for religious organizations. Some are even suggesting protections for individuals and small businesses who offer services for weddings — like photographers, florists, caterers, bakers, wedding planners and musicians. The argument is that these individuals and businesses might have religious objections to gay couples' marrying and could be exposed to sizable fines or strong penalties under nondiscrimination statutes.

The deliberations in New Hampshire could have implications for New York, where the legalization of same-sex marriage hovers on the brink without the kind of protection for religious groups that Lynch demanded. New Hampshire's experience may also affect current debates in the District of Columbia and Rhode Island.

Opponents of same-sex marriage have frequently said it threatens to penalize members of the clergy who refuse to solemnize such unions or who preach against them. Legal experts almost unanimously dismiss such alarms. Refusals to officiate or to mute a religious doctrine, they say, are solidly protected by the First Amendment.

But that is not where the real issue lies. What would be the impact of legalizing same-sex marriage on a broader range of religious institutions?

Would Catholic universities now providing housing for married couples be required to accommodate same-sex couples? Would church or synagogue facilities used for wedding receptions have to be equally available for same-sex celebrations? How would provisions forbidding discrimination on the grounds of marital status affect employment and benefits policies or adoption services like the specialized adoption services that Catholic Charities in Massachusetts suspended after the state legalized same-sex marriage and ordered the church group to place children with gay couples?

Connecticut and Vermont addressed at least some of these questions in their recent bills legalizing same-sex marriage. Religious dissenters from such marriages, they stated, "shall not be required to provide services, accommodations, advantages, facilities, goods or privileges" if the request "is related to the solemnization of a marriage or celebration of a marriage."

Connecticut also extended protections to religious adoption agencies, and Lynch spelled out other exemptions related to counseling, courses, retreats and housing by religious institutions.

What about self-employed individuals or small businesses that offer services for weddings — the "little guy," as Robin Fretwell Wilson, a law professor at Washington and Lee University, puts it.

Wilson is an editor of "Same-Sex Marriage and Religious Liberty: Emerging Conflicts" (Rowman & Littlefield, 2008) and one of a group of legal scholars urging states considering legalizing same-sex marriage to include "robust" protections for religious conscience.

These scholars have divided views on the wisdom of same-sex marriage itself. Wilson, for example, has taken no position on it, while Douglas Laycock, another editor of that volume and a foremost analyst of First Amendment religious liberty questions, strongly supports it. Laycock considers that support compatible with his advocacy of religious exemptions. They are "parallel protections," he believes, "for quite similar claims to individual liberty in matters essential to personal identity."

Writing to officials in New York, Laycock pointed out that it was not "in the interest of the gay and lesbian community to create religious martyrs when enforcing the right to same-sex marriage."

"It is far better," he wrote, "to respect the liberty of both sides and let same-sex marriage be implemented with a minimum of confrontation."

Exactly how great is the potential for confrontation? Marc Stern, the longtime legal counsel and now acting co-executive director of the American Jewish Congress, thinks there are multiple possibilities and joined Laycock in writing to New York officials.

Many states already have a welter of laws prohibiting discrimination on grounds of moral status and sexual orientation in employment, housing, services by licensed professionals and public accommodation. Some of these laws have religious exemptions; some do not. Legalizing same-sex marriage could ratchet these up in complicated ways, creating the possibility of expensive litigation, some advocates of clear-cut protection for religious objectors say.

Or maybe not. Dale Carpenter, who teaches at the University of Minnesota Law School and is a conservative advocate of same-sex marriage, believes that recent experience with either same-sex marriage, civil unions or plain-vanilla provisions against discrimination on grounds of sexual orientation shows very few "legal conflicts between gay couples and religious objectors."