Italy's Constitutional Court blocks a referendum to free cannabis from the drug law

In February 1981 Italy’s Constitutional Court stopped a referendum that would have taken cannabis out of the drug law. More than half a million people had signed for it. The court did not question the signatures. It ruled that voters could not repeal rules Italy needed to keep its promises under the 1961 UN drug treaty.

The petition

On 26 June 1980 five promoters handed in a petition asking voters to delete the parts of the 1975 drug law that named cannabis: the clauses putting THC and cannabis on the lists of controlled drugs, Indian hemp in the ban on growing, and cannabis in the checks on imports. The court read the aim plainly, helped by the promoters’ own brief: to free the growing, trade, possession and use of hashish and marijuana.

In December the referendum office at the Court of Cassation confirmed that the petition had more than 500,000 valid signatures.

Why voters could not decide

Article 75 of the Constitution rules out referendums on laws that authorise the ratification of treaties. The promoters’ lawyer, Mauro Mellini, argued that the 1975 law was no such law, and that the treaties did not require Italy to treat cannabis the way it did.

The court looked at the 1961 Single Convention and its 1972 protocol, which Italy had ratified without reservations in 1975. The convention puts cannabis and its resin in Schedule I, and also in Schedule IV, kept for drugs with particularly harmful properties. It obliges each country to limit their growing, trade, possession and use to medical and scientific purposes, and to make breaches punishable.

Treaty rules are for parliament

The court then widened the Article 75 ban. It covered not only ratification laws but also rules a treaty makes compulsory, where the state’s only choice is to obey the treaty or break it. Laws that merely choose how to carry out a treaty could still be put to a vote. Breaking a treaty makes the state answer to the other countries that signed it, the court said, and the Constitution leaves that judgment to parliament.

Repealing the cannabis clauses would plainly breach the Single Convention, so the court declared the referendum inadmissible. The 1975 controls stayed in place.

What came next

A year later the court also upheld the law’s penalties for larger amounts (1982). A 1993 referendum with a narrower aim, the criminal penalties for personal use, did reach voters and passed. The treaty argument came back in 2022, when the court blocked a referendum on home growing. Today’s rules are on Italy’s country page.^[1]