This was an appeal against the judgment of the Montpellier Court of Appeal, Chamber correctional, of 23 September 2014, which convicted Olivier X and William Y, both British nationals, of degradation or aggravated deterioration of the property of others and fined them. On 4 June 2010, several activists of the Greenpeace movement led an operation in the Mediterranean Sea to demonstrate their opposition to bluefin tuna fishing. In boats flying the Dutch flag, they approached three tuna vessels flying the French flag which were fishing in international waters. They placed sandbags on the edges of a very large seine net attached to one of the tuna boats, in order to unbalance the net and free the caught fish. Clashes broke out between Greenpeace activists and the tuna crew. Calm returned with the intervention of a French naval vessel. The seine net suffered damage. After a criminal investigation, Stichting Greenpeace Council, a legal person under Dutch law having its registered office in the Netherlands, as well as X and Y, the alleged organisers and masterminds of the operation, were cited, convicted and sentenced before the Montpellier Criminal Court on the counts of deterioration or aggravated deterioration of the property of others.

The first ground of appeal alleged violation of arts 92 and 97 of UNCLOS, art 1 of the International Convention for the Unification of Certain Rules relating to Penal Jurisdiction in Matters of Collision or other Incidents of Navigation 1952 (the Collision (Penal Jurisdiction) Convention 1952), arts 113-2, 113-3 and 113-12 of the Penal Code, and arts 689, 591 and 593 of the Code of Penal Procedure. The appellants argued that it follows from arts 92 and 97 of UNCLOS and art 1 of the Collision (Penal Jurisdiction) Convention 1952 that in the event of a collision or any other navigation event involving a seagoing vessel of such a nature as to engage the criminal liability of the master or any other person in the service of the ship, prosecutions can only be brought before the judicial authorities of the State whose flag the ship was flying. The offences prosecuted were not committed on ships, but on the high seas, and therefore fell within a 'navigation event' within the meaning of these Convention provisions. The application of these provisions excluded the jurisdictional competence of the French courts. French criminal law, in the application of art 113-12 of the Penal Code, is applicable to offences committed beyond the territorial sea only if the international Conventions and the law so provide. The Court of Appeal disregarded the rules governing the territorial application of criminal law.

Held: Appeal allowed.

The Court of Appeal was right to rule out the application of arts 92 and 97 of UNCLOS, which in the case of collision or any other maritime navigation incident on the high seas liable to engage the criminal liability of a master or crew member, attribute jurisdiction to the criminal courts either of the flag State or of the State of which the person concerned is a national, provided that the collision, within the meaning of that Convention, means an accidental collision between two ships. Deliberate damage does not come within the definition of incidents of navigation. The Court, moreover, rightly rejected the application of the Brussels Convention of 10 May 1952 which fixes the rules of jurisdiction concerning the protective seizure of seagoing vessels.

The Court of Appeal correctly applied art 113-3 of the Penal Code, in terms of which French law is applicable to offences committed against ships flying the French flag. The seine net, which was damaged as a result of voluntary action by Greenpeace activists, constitutes an accessory and an extension of the vessel to which it is attached, and is subject to the same legal status as the ship itself.

However, any judgment must include specific reasons to justify the decision. The insufficiency or contradiction of reasons is equivalent to their absence. The judgment held X and Y guilty of degradation or aggravated deterioration of the property of others, holding that the defendants were the organisers and masterminds of the operation and that they gave the orders necessary for the conduct of operations to the militants who came into contact with French tuna vessels. But by pronouncing thus, without characterising against each of them material acts constituting degradation or deterioration, and without better explaining their respective degrees of implication as the author or, if necessary, the accomplice of the action thus undertaken, the Court of Appeal did not justify its decision.

Legal persons, with the exception of the State, are criminally responsible for offences committed, on their behalf, by their organs or representatives. To justify the criminal responsibility of Stichting Greenpeace Council, the judgment holds that this legal person was the organiser of the operation, for which it had provided the logistics and the necessary means, and that it had mandated Olivier X and William Y to direct the operation on site. But from these reasons alone, it does not follow that the damage was committed on behalf of the relevant legal person by its representatives. The Court of Appeal did not justify its decision.

The judgment of the Montpellier Court of Appeal, dated 23 September 2014 is therefore struck down and annulled, and the case is to be tried again in accordance with the law. The case is sent back to the Paris Court of Appeal for rehearing.