Carl and Angel Larsen, from Minnesota, and their company, Telescope Media Group, filed an appeal on Friday to challenge a state law that allows the government to control the stories they tell.
According to ADF International, which is legally representing the couple, the law allows Minnesota to punish the Larsens with fines and jail time "if they create wedding films consistent with their Christian faith while declining to create wedding films promoting contrary views".
ADF added that they asked a federal district court to get rid of the law while their case proceeds. However, the court denied that request and instead ruled in favour of the state's motion to dismiss the lawsuit, which was filed in 2016.
The Larsens have asked the US Court of Appeals for the 8th Circuit to reinstate their lawsuit.
ADF Senior Counsel Jeremy Tedesco said: "The government shouldn't threaten artists with fines and jail simply for living in accordance with their beliefs in the artistic marketplace.
"Americans should have the freedom to disagree on significant matters of conscience, which is why everyone, regardless of their view of marriage, should support the Larsens.
"Government is supposed to be freedom's greatest protector, not its greatest threat. That's why we are asking the 8th Circuit to reverse the district court's decision."
Minnesota Department of Human Rights officials have stated that penalties for violation of Minnesota Statutes Chapter 363 include payment of a civil penalty to the state; triple compensatory damages; punitive damages of up to $25,000; a criminal penalty of up to $1,000; and even up to 90 days in jail.
"The Larsens will create films for anyone. They just cannot create films promoting every message," the opening brief for the appeal explained.
"Their decision turns on what a film promotes, never who requests it. This shows the Larsens are no different from 'a ghost-writer' who declines to 'write a book [concerning a person's protected status] when the writer disagrees with the message the book would convey....'
"According to the district court, that would be objecting to 'the message of the book, not...the sexual orientation of the customer....' Yet it refused to accept this same distinction for the Larsens."
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