Senator Mike Lee (Photo by Leigh Vogel/Getty Images)

Republicans in Congress have filed a Supreme Court brief arguing that religious freedom and free speech protections give people the right to discriminate against homosexuals.

GOP lawmakers in the House and Senate announced today that they would file an amicus brief in an upcoming Supreme Court case involving a baker who refused to make a cake for a same-sex couple.

Jack Phillips of Colorado’s Masterpiece Cakeshop is attempting to undermine a state-level law that protects LGBT people from discrimination, on the grounds that he has a constitutional right to ‘religious freedom’ and ‘free speech’.

The baker continues to insist his Christian faith requires discrimination against gay people, and insists that Jesus Christ would have refused to make a cake for gay people too.

Phillips is supported by Alliance Defending Freedom, a fundamentalist Christian law firm which strongly opposes discrimination protections for LGBT people.

The GOP will support the baker’s claim when the case goes before the Court, which sits from next month.

Donald Trump’s Supreme Court justice Neil Gorsuch, an ultra-conservative, threatens to tip the balance of the court against LGBT rights, which could lead to a decision that undermines discrimination protections nationwide.

According to The Hill, so far 86 Republicans from across Congress have given their backing to a brief in support of the baker.

Senator Mike Lee told reporters that it was a matter of ‘free speech’ as well as religious freedom.

He said: “As a matter of legal doctrine this is a compelled speech case.

“The Supreme Court has said the First Amendment, in addition to doing all the other things that it does, prohibits the government from requiring individuals to make a particular statement with which they disagree.

“The government cannot force you to speak where you would choose to remain silent. It cannot make a statement with which you firmly fundamentally disagree. These are foundational pillars of the American legal system and our Constitution.”

Phillips’ law firm, Alliance Defending Freedom, has sought to undermine LGBT rights protections in a number of states.

Though the ADF is framing the issue around a religious objection to same-sex marriage, their other cases show a much wider support for anti-LGBT discrimination.

For instance, they have sued a school district over a transgender non-discrimination policy, and defended a T-shirt printer who refused an order from a Pride celebration.

The gay couple who were discriminated against by Phillips, David Mullins and Charlie Craig, have vowed to stand up for equality.

They said: “This has always been about more than a cake. Businesses should not be allowed to violate the law and discriminate against us because of who we are and who we love.

“While we’re disappointed that the courts continue debating the simple question of whether LGBT people deserve to be treated like everyone else, we hope that our case helps ensure that no one has to experience being turned away simply because of who they are.”

The American Civil Liberties Union and the ACLU of Colorado represent Mullins and Craig in the case.

James Esseks, director of the ACLU’s LGBT Project, said: “The law is squarely on David and Charlie’s side because when businesses are open to the public, they’re supposed to be open to everyone.

“While the right to one’s religious beliefs is fundamental, a license to discriminate is not.

“Same-sex couples like David and Charlie deserve to be treated with the same dignity and respect as anyone else, and we’re ready to take that fight all the way to the Supreme Court.”