The lawsuit charged that the anti-discrimination law as interpreted by the civil rights commission would compel the church to "communicate government messages to which it objects" and force the church to "use its building in violation of its religious beliefs."
Some experts criticized the church's legal action, but acknowledged there was ground to believe the law could affect church operations.
Prof. Paul Gowder, a constitutional expert at the University of Iowa Law School, said it would be "blatantly unconstitutional" for state officials to try to regulate church sermons. He told the Des Moines Register it is "absurd on its face" to think the commission would prohibit a church from sermonizing.
However, he said access to church bathrooms by those who identify as transgender is more complicated, given jurisprudence that sees churches as non-exempt from general laws that apply to everyone under the U.S. Constitution.
"So I guess the honest answer to the bathroom question would be I am not sure," Gowder said.
Law professor Maura Strassberg of Drake University said the U.S. Supreme Court has ruled that public facilities' decisions on allowing someone to use a restroom are not considered free speech and would not be protected by the First Amendment.
She argued that there are situations where a preacher's remarks could become harassment.
"There is a line: You can go from, 'This is what God believes' … to 'You are bad, so we don't want you here'," she said.
However, Holcomb said these professors overlooked the "critical" constitutional principle of church autonomy.
"The Supreme Court has recognized again and again that the state has no jurisdiction to intrude into internal church matters, which include not only teaching its religious beliefs, but also operating its house of worship consistently with those beliefs," she said.
"Churches order their houses of worship to reflect and reinforce their religious teaching. They are not businesses, they are not public accommodations: they are inherently sacred spaces, and enjoy special protections under the religion clauses."
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Ben Hammes, a spokesman for Iowa Gov. Terry Branstad responded to the legal challenge. He said that Governor Branstad "has confidence in the commission to enforce the laws we currently have that protect religious institutions' right to exercise a religious exemption while protecting personal rights."
Kevin J. Jones is a senior staff writer with Catholic News Agency. He was a recipient of a 2014 Catholic Relief Services' Egan Journalism Fellowship.