Europe is facing a growing debate over whether to restrict the rights of Muslims to preserve the continent’s secular values. A new court ruling could make that easier.

The verdict Tuesday from the European Court of Justice, the top authority on European Union law, said that a Belgian company was free to bar Muslim women from wearing headscarves at the office. That potentially opens the door to more restrictions on religious expression in the workplace, as employers have now been told that such rules can be consistent with EU law.

The corporate security firm at the center of the case, G4S, employed a Muslim receptionist, Samira Achbita. Achbita asked permission to wear a headscarf. G4S refused, and afterward issued a formal rule that barred all employees who dealt with clients from wearing visibly identifiable religious garb, including Jewish kippahs and Christian crosses.

The European court, in a ruling announced on Tuesday, came down mostly on G4S’s side. The reason, it explained in a press release on the case, is that the company’s rule didn’t single out headscarves, and so did not constitute anti-Muslim discrimination.

The problem is that G4S’s rule burdens some members of minority groups, such as Muslim women and Jewish men, far more than other people — Christians are not religiously obligated to display signs of faith.

The ECJ did acknowledge that this, in theory, could constitute a kind of “indirect” discrimination, and asked the Belgian court to investigate further to see if there was some kind of discriminatory intent in G4S’s specific rule.

But the European court ruled that rules that indirectly burden one group more than others can be acceptable provided the company had a good reason for it. In G4S’s case, that meant projecting an image of religious neutrality to its clients. If that’s why the company did it, the ECJ said, then it’s A-okay.

“The ban on the visible wearing of signs of political, philosophical, or religious beliefs is appropriate for the purpose of ensuring that a policy of neutrality is properly applied, provided that that policy is genuinely pursued in a consistent and systematic manner,” the court ruled.

It’s a ruling speaks to the expansive vision of secularism that prevails in some European countries — one that, in turn, explains how Europe’s anti-immigrant far right has risen by, in part, selling itself as a defender of liberal values. And on Wednesday, one of the principal advocates of this vision, the Netherlands’ Geert Wilders, is standing for election.

The court’s ruling show how secularism links up with the far right

Few Americans would see a receptionist at a company like G4S wearing a headscarf and assume, automatically, that this said anything about the company’s position on religion. Americans typically assume that religious expression is a private affair, and neither the state nor an employer has the right to interfere with it. (The US military, which has on-again, off-again restrictions on its troops’ head coverings, is an exception.)

In some European countries, there’s a sense that widespread Muslim immigration is threatening secular European culture. They worry not only about freedom of religion but also freedom from religion — a commitment to limiting religious influence on public life and in the public sphere. This is particularly pronounced in France and other French-speaking countries, such as Belgium.

This vision of secularism creates tension with European ideals about tolerance and diversity. On the one hand, Europeans look at things like the growing numbers of Muslim women wearing headscarves, and see the spread of patriarchal values that many Europeans see as outdated and oppressive. On the other, they oppose singling out minority groups, particularly nonwhite minorities, in laws restricting freedom of expression.

This is why headscarf bans happen and why they are also framed as “neutral” policies affecting all religious groups. In 2004, France banned schoolchildren from wearing religious garb to class. The rule was obviously designed to target Muslim girls wearing headscarves, and everyone knew it — but the rule was worded in a neutral fashion, applying to all religions, to get around anti-discrimination laws.

This basic tension between European secularism and tolerance is one of the key factors fueling the rise of Europe’s xenophobic far right. If you look at leaders like the Netherlands’ Geert Wilders or France’s Marine Le Pen, they often position themselves as defenders of secular “European” values. They argue that the only way to maintain a society that’s both tolerant and secular is to restrict immigration from Muslim-majority countries and restrict the rights of the Muslims already in Europe.

"Politicians from almost all established parties are promoting our Islamization,” Wilders said in a January speech. "Day after day, for years, we are experiencing the decay of our cherished values. The equality of men and women, freedom of opinion and speech, tolerance of homosexuality — all this is in retreat.”

The ECJ ruling is at least a temporary victory for this vision — suggesting that when there’s tension between tolerance and secularism, the laws of secularism deserve to win out. The political appeal of such restrictions is in for a major test on Wednesday.