In law as in Shakespeare, what’s past is often prologue.

Arkansas “patriot” Jan Morgan announced to the world two years ago that her gun range would no longer serve Muslim customers. At the time, I noted that her actions violated public accommodation law and that she would lose an inevitable lawsuit; that did not deter Morgan, and it did not deter a number of other gun-range owners from implementing the same policy.

But Chad and Niki Neal might soon wish they hadn’t followed Morgan’s example. The couple, who own Save Yourself Survival and Tactical Gun Range in Oktaha, Okla., posted a sign in a shop window declaring, “This privately owned business is a Muslim Free establishment.” Last year, they allegedly cited this policy when they turned Raja’ee Fatihah away after he identified himself as a Muslim.Unfortunately for the Neals, Fatihah is a U.S. Army reservist and investigator for the Oklahoma Department of Human Services. The American Civil Liberties Union (ACLU) and the Council on American-Islamic Relations (CAIR) have now filed suit on his behalf. (Fatihah sits on the board of CAIR’s Oklahoma affiliate.)

“Whether the sign in question says ‘no Muslims’ or whether it says ‘no coloreds’ or whether it says ‘no women’ or ‘no Christians’ or ‘no Buddhists’ ... it is just as un-American and, fundamentally, it is just as wrong,” the ACLU’s Brady Henderson told the Associated Press (AP).

Robert Muise, an attorney for the Neals, claims his clients told Fatihah to leave because he became “belligerent.”“The law does not require a gun shop or gun range owner – owners of an inherently dangerous business – to equip or train the next jihadist,” he told Reuters.

In separate comments to the AP, he claimed that, “The only thing the law prohibits is if somebody denies services strictly on the basis of religion, and that didn’t happen here.”

But Fatihah says that isn’t what happened. At a press conference, he said the Neals treated him like any other customer until he mentioned his faith. “Shooting is something I do as a hobby, and I also practice to keep up my skills as a reservist,” he explained. “When I went to the range, it went normally until I told them I was Muslim.”

The Neals’ sign appears to support Fatihah’s discrimination claim, and so do their public Facebook postings. In an August 19, 2015 post apparently published in response to brewing controversy over Fatihah, Niki Neal claimed that “No person has ever been turned away from Save Yourself Survival and Tactical Store for discrimination of any kind” and that individuals from “…every race, and religion are welcome at our store so long as our safety rules, and our store policies are observed.”

But in a follow-up comment on the same post, her husband and business co-owner stated that the ban on Muslims would remain in place. He cited Morgan’s 2014 policy as justification for the decision.

It seems that the Neals and their attorney cling to two false beliefs: that they have a legal right to ban Muslims from their business, and that it is not discriminatory for them to do so. These beliefs aren’t unique to the Neals. Many far-right activists (including Morgan) claim that Islam is a hostile political or military entity, not a religion, and that it has no claim to First Amendment protection.

But courts have rejected this argument wherever it has been raised. The law is clear: As the owners of a secular, for-profit business, the Neals have a legal obligation to serve Muslims. If Fatihah’s account is accurate, their failure to adhere to the law resulted in demonstrable harm and they are unlikely to win in court.

That should be a warning to gun-range owners with similar policies. Pluralism is a reason to love America, not a reason to violate its laws.