After President Donald Trump issued his noxious “Muslim ban” executive order Jan. 27, Americans United promised to oppose it.

And we are. Last night, AU’s Legal Department filed a friend-of-the-court brief arguing that the Trump order violates the First Amendment’s separation of church and state in the case challenging the ban brought by the states of Washington and Minnesota. And earlier today, AU attorneys caught a flight to Seattle to be in court for a hearing on Washington’s request for a temporary restraining order against the Trump directive.

After Trump signed the executive order, people from seven Muslim-majority countries were deported or detained at airports across the country. As chaos unfolded, people from all walks of life and all faiths rushed to the airports around the country to protest. This included lawyers who offered legal assistance to those in need. Since then, lawsuits challenging the ban have been filed in several courts, many of which have already successfully won restraining orders. State of Washington and State of Minnesota v. Trump is the first case in which U.S. states are taking a stand against the federal government.

Trump's Muslim ban won't survive in court if AU has its way.

AU’s brief addresses how the executive order violates the religious freedom rights of Muslims and is an affront to the fundamental principles of the First Amendment. The cases are rapidly unfolding, but this may be the first court filing that specifically focuses on these important arguments.

The brief explains that the Muslim-ban executive order singles out Muslims from seven Muslim-majority countries for punishment, based on their faith, and gives preference to religious minorities in those countries—in other words, non-Muslims. This violates the constitutional principle barring the government from singling out one particular faith for sanction or giving preference to any one faith over another.

But the Trump order does more than that: It also assaults our fundamental values. By subjecting people to ill treatment because of what faith they practice, the order strikes at the very heart of country’s promise of religious freedom.  As the brief explains, “No amount of rebranding will change” the fact that people are facing grave harm “for no reason other than their deity and preferred holy book.”

This fight is just getting started, and AU’s bringing our expertise defending the Constitution’s protections for religious freedom to the fight. Stay up with our work and sign up for email updates here.