The Supreme Court has heard that the owners of Ashers Baking Company found to have discriminated for refusing to make a pro-gay marriage cake were forced to act against their religious beliefs.

The Supreme Court appeal also heard that the family-ran bakery has been punished by the state for refusing to make the controversial cake.

Ashers Baking Company, a small chain of bakeries ran by the McArthur family, declined an order placed by customer and gay rights activist Gareth Lee at its Belfast city centre shop in May 2014.

Read More: There will be no winner in Northern Ireland's absurd gay cake scrap 

Lee later sued and was awarded £500 by the bakery.

As the appeal opened today, the McArthur family's barrister David Scoffield QC stressed their deeply-held views on marriage.

Read More: Belfast gay cake scrap is discrimination in action

General Manager Daniel McArthur and his wife Amy of Ashers Baking Company attended the hearing.

"This is a case of forced or compelled speech, unlike other cases which have come before the court," Scoffield told the Supreme Court.

The Equality Commission has spent £150,000 on ‘gay cake’ case.

Legal bill of Ashers bakery is £200,000.

Total: £350,000.

And that doesn’t include legal costs of today’s Supreme Court hearing.

— Mark Simpson (@BBCMarkSimpson) May 1, 2018

Lee's barrister said that the man had "no abusive intent" in placing the order in 2014. 

Read More: Why Ashers Bakery vs Gay rights advocate court case is a big deal 

Lee had requested a cake that included a slogan that said "support gay marriage" along with a picture of Bert and Ernie from Sesame Street, and the logo of the Queerspace organization that he aligns with.

Ashers “gay cake” case: bakery owners said Equality Commission pushed for interpretation of law which extinguishes conscience.

— michael mchugh (@mmchugh02) May 1, 2018

Daniel McArthur from Ashers bakery outside Supreme Court on refusal to make ‘gay cake’:

“The Equality Commission has pushed for an interpretation of the law which extinguishes conscience.

“They seem to think that some people are more equal than others.”

— Mark Simpson (@BBCMarkSimpson) May 1, 2018

"Mr and Mrs McArthur have been penalised by the state, in the form of the judgment at the county court, for failing through their family company to create and provide a product bearing an explicit slogan 'Support Gay Marriage' to which they have a genuine objection in conscience," Scoffield added.

Five Supreme Court justices must now reach a judgement.

According to the BBC, It could be February 2019 before they make up their minds.