Duplomb Law, reconstruction of Mayotte, municipal elections... These texts on which the decisions of the Constitutional Council are eagerly awaited Thursday

The Constitutional Council delivers its verdict. The Wise Men are expected to determine, starting at 6 p.m. on Thursday, August 7, whether several recently adopted and highly criticized laws are constitutional. In a tense political and social climate, the decisions will be closely scrutinized. From the Duplomb agricultural law to electoral reform in Paris, Lyon, and Marseille, franceinfo takes a look at the relevant texts.

The Duplomb agricultural law

This text provides for the conditional reintroduction of a neonicotinoid pesticide, acetamiprid. Harmful to biodiversity, it is nevertheless authorized elsewhere in Europe, and its return is being called for by the FNSEA, the country's largest agricultural union, to protect the beet and hazelnut industries from aphids. The law also relaxes the construction of water reservoirs, mega-basins, and intensive livestock buildings. The debates surrounding this text, and then its adoption, sparked strong opposition from civil society. A petition posted on the National Assembly's website has surpassed two million signatures, a record.

For their part, left-wing parliamentarians raise several concerns of unconstitutionality, considering it incompatible with environmental preservation and the precautionary principle in matters of health. "In general, the Constitutional Council tries to reconcile environmental imperatives with economic freedom, to undertake," Thibaud Mulier, a specialist in public law, reminds franceinfo. However, according to political scientist Benjamin Morel, it is possible that the institution will invoke "the principle of environmental non-regression." "In 2020, they had already validated the reintroduction of neonicotinoids on the grounds that it should be temporary, until 2023," continues the lecturer in public law at the Panthéon-Assas University. If they decided that environmental protection should take precedence, they could censor the article on the controversial insecticide, without this having any impact on the rest of the law.

Critics of the text also denounce the way in which the law was adopted, with the vote of a preliminary motion of rejection in the Assembly that prevented any debate or submission of amendments by the deputies. If the Sages considered that this procedure was unconstitutional, they could censor the entire law. "This would be a scathing disavowal" for the executive, believes Thibaud Mulier, without however believing it too much. "It would be a reversal of jurisprudence," confirms Benjamin Morel, "dubious" about this prospect. "The Sages would have to be able to probe the minds and the hearts to establish whether the motion of rejection was used to circumvent the deputies' right to amend."

Whatever the Council's decision, the matter will not be closed. Even a partial censorship would be interpreted as a victory for environmentalists and would fuel the anger of the main agricultural unions , while validation of the text would risk rekindling citizen mobilization at the start of the school year. The government has not closed the door to a new debate in Parliament following the success of the petition, while ruling out a postponement of promulgation after the possible green light from the Sages.

The law on municipal elections in Paris, Lyon and Marseille

More technical, the so-called "PLM" bill for Paris-Lyon-Marseille aligns the municipal voting system in these three metropolitan areas with that of other municipalities, removing the specificities of the districts. The text, led by Macronist Sylvain Maillard and supported by the executive, was rejected twice by the Senate, where its detractors from both the left and the right denounce electoral manipulation and a forced passage, less than a year before the municipal elections. The reform has accentuated divisions within the central bloc, including within the government: Bruno Retailleau, Minister of the Interior and therefore in charge of elections, did not wish to defend the reform, despite it being called for by his colleague at Culture, Rachida Dati, candidate for mayor of Paris.

The main legal flaw is that of financial inadmissibility, according to constitutional experts. "This text creates additional expenses when parliamentarians do not have the right to do so, in the name of Article 40 of the Constitution," analyzes Thibaud Mulier. Indeed, by establishing two separate elections in these three cities, compared to just one currently, this law would generate additional costs (printing of ballots and official propaganda, multiplication of candidates and therefore campaign expenses, etc.) "If the Council wants to censor, it will have an angle of attack," summarizes Benjamin Morel. This argument would bring down the entire law.

Other grievances against the text, such as inequality between municipalities, the risk of a lack of clarity in the vote, or the fact that the reform is too close to the 2026 election, are, however, considered more fragile by the two constitutional experts interviewed by franceinfo, in light of the Council's case law. The timetable is tight: the decision will be made just a few days before the opening of the pre-election period for the municipal elections, on September 1.

The law for the refoundation of Mayotte

An organic law and a planning law were adopted to rebuild Mayotte after Cyclone Chido in December. While these texts are eagerly awaited by the local population, several anti-immigration measures in the planning law are in the sights of Green, Insoumis, and Socialist MPs. These include the tightening of the criteria for obtaining a residence permit for foreign parents of children born in Mayotte. Furthermore, so-called "informal" housing will no longer be considered housing eligible for family reunification.

"A provision authorizes the administrative detention of a foreigner accompanied by a minor, which is an exception to common law, and it is also a possible violation of the best interests of the child," emphasizes Thibaud Mulier. He points out that, in the past, the Sages have already admitted "exceptional situations for Mayotte" for the reform of obtaining nationality , in May. Censorship of this section would represent a snub to Bruno Retailleau, who has made the fight against immigration his priority.

The law on the detention of foreigners deemed dangerous

The Minister of the Interior will also carefully scrutinize the decision of the Sages on the text adopted after the murder of Philippine , a 19-year-old student whose body was found in the Bois de Boulogne in 2024. The suspect, an illegal Moroccan already convicted of rape, was subject to an obligation to leave French territory (OQTF) but had been released from an administrative detention center a few weeks before the murder.

The bill adopted on July 9th allows for the extension of the detention period for foreigners deemed dangerous, from the current 90 days to 210 days. Bruno Retailleau hailed "a major step forward" and "a law that can save lives." But the left and associations including France Terre d'Asile and Cimade denounced the text as "demagogic," "which weakens our rule of law."

The text also includes the detention of certain asylum seekers "whose behavior constitutes a threat to public order" and the possibility of taking fingerprints and taking identity photos under duress, in order to facilitate identification. These measures were included in the immigration law adopted in 2023. However, the Sages judged at the time that many of the measures were "legislative riders," with no direct link to the text, and largely censored the law.