France’s Constitutional Council struck down large chunks of a tough new immigration law on Thursday, issuing a widely expected ruling that many provisions added by President Emmanuel Macron’s government under right-wing pressure were unlawful.

But legal experts said the ruling, which relied heavily on procedural arguments, would do little to settle France’s raging immigration debates.

The nine-member council, which reviews legislation to ensure that it conforms to the Constitution, said in a statement that it had partially or completely struck down over a third of the 86 articles in the law, which was passed in December. Among them were restrictions on foreigners’ access to government subsidies and limitations on the reunification of migrant families.

Overhauling France’s immigration rules was one of Mr. Macron’s second-term priorities, and under ordinary circumstances, the council’s decision could be seen as a stinging rebuke. The French leader had called the new law a “shield” to deal with the pressure of migrants illegally entering the country.

But because of the way the law came to pass and the nature of the measures that were rejected, the ruling may paradoxically give Mr. Macron some relief. Gérald Darmanin, Mr. Macron’s interior minister, welcomed the council’s decision, saying it had left intact the heart of the law.

“We have all the resources that we need” to be “very strong on integration” and “very harsh against foreign criminals,” Mr. Darmanin told TF1 television.

Many of the measures struck down by the council had been included in the law only after the government reached a compromise with France’s mainstream right-wing opposition party, the Republicans. The deal was needed to get the bill through the lower house of Parliament, where Mr. Macron’s party and its centrist allies do not hold an absolute majority.

The compromise handed Mr. Macron a legislative victory but introduced many hard-line measures that were not part of his government’s original plans, like delaying non-European foreigners’ access to housing aid or family allowances for months, even years. It also attracted the unwanted support of the far-right National Rally party and caused cracks in Mr. Macron’s governing alliance, with some of his own lawmakers voting against the bill.

The government was left in the awkward position of acknowledging that it disagreed with some of the measures — like a rule forcing foreign students from outside the European Union to pay a new deposit fee — or, worse, that parts of a law that it had championed might violate the Constitution.

The Constitutional Council struck down most of the measures on procedural grounds, arguing that they were legislative riders that had been wrongly tacked on to the government’s bill. It rejected only a handful — like the creation of yearly immigration quotas set by Parliament — on their merits.

By taking that approach, legal experts said, the council did not set a strong legal precedent, and did not say whether stringent anti-immigration measures favored on the right and far right were compatible with France’s rule of law.

“One is left a bit hungry for more substance,” said Anne-Charlène Bezzina, an associate professor of public law at the University of Rouen.

The ruling could further fuel debates on immigration, she said, especially longstanding demands from the right to change France’s Constitution.

Marine Le Pen, the French far-right leader, said in a statement after the ruling that “only an overhaul of the Constitution will make it possible to respond to the migratory challenges that are hitting our country so hard.”

Others hailed the decision.

“For us this is a relief,” Cyrielle Chatelain, a top lawmaker from the Green party, told reporters at the lower house of Parliament. The ruling, she said, will prevent tens of thousands of foreigners who legally live and work in France from suddenly losing subsidies.

Mr. Macron’s opponents on the left had accused his government of pushing through measures that it knew would not pass muster with the Constitutional Council purely to score political points. Even Laurent Fabius, the president of the council, had expressed frustration, saying this month that the institution was not a “chamber of appeal for the choices made by Parliament.”

Unlike the Supreme Court in the United States, the Constitutional Council is not at the top of France’s court system, and none of its members are judges. Instead, they are a mix of legal experts, former politicians and high-ranking civil servants.

Around France, france/article/2024/01/15/opponents-of-france-s-immigration-law-take-to-street-protests_6433872_7.html” title=””>thousands marched last week to protest against the new law, and more demonstrations were held on Thursday. Human rights associations, left-leaning parties and labor unions called the ruling a victory and asked the government to scrap the law entirely — an unlikely outcome, as Mr. Macron is now expected to officially enact it.

Mr. Macron’s government had initially presented its immigration bill as both a carrot and a stick that would streamline a sluggish asylum process and facilitate the deportation of migrants who are in France illegally or who commit crimes while also facilitating integration. The law, for instance, creates temporary residency permits for foreign workers in fields experiencing labor shortages.

But the compromise with the right-wing Republicans had gnawed away most of the carrot and made the stick much bigger, even including snippets of many longstanding far-right stances on immigration.

These included toughening family reunification rules for immigrants and forcing children born to foreigners in France to request citizenship upon reaching adulthood, rather than having it granted automatically.

Many of those measures were struck down by the council, bringing the law roughly back to what the government had initially intended.

Samy Benzina, a public law professor at the University of Poitiers, said that the council had made a “strategic choice” to rule mostly on procedural grounds to get out of a tricky political situation.

“It saves it from having to rule on the substance of the law, which is always delicate,” he said. “This is not a ruling that will go down in history because it defended human rights.”