By opposing a gay- and trans-inclusive anti-discrimination ordinance, members of the Utah Legislature want to maintain special rights currently given to homophobes and heterosexists.
Under state law, racists may not fire someone simply because of his or her race, at least not legally. Chauvinists may not refuse to rent an apartment to someone simply because of his or her gender. Likewise, if I change religions to become a Hare Krishna, City Weekly founder John Saltas can't fire me just because of that.
Salt Lake City simply wants to give no more--and no fewer--rights to homophobes than are already given to racists, chauvinists, and bigots of all stripes. There's nothing all that special about that. But the Legislature wants to preserve homophobes' "special" rights to discriminate against the minority group that they don't like.
The coming months could be hilarious and sad. Salt Lake City is almost sure to pass their ordinance, putting the ball in the Legislature's court. As far as I understand it, the Legislature has full power to revoke the city's ordinance--in a sense--and may choose to do so to appease conservative constituents. But just prior to the bill's passage, it will be the Legislature that will need to debate whether they want to give "special" rights to homophobes.