Now the Court of Justice has handed down a second judgment in answer to a request for a preliminary ruling from a Swedish court that confirms and consolidates that position. In its recent judgment in Case C-142/05 Mickelsson and Roos the Court of Justice held that Swedish rules on the use of jet-skis on navigable waterways were caught by the prohibition of measures hindering the free movement of goods in Article 28 EC but could be justified under Article 30 EC.
There had been divergent opinions of Advocate generals on that point. In her opinion in this case Advocate General Kokott seemed to favor taking product use regulations outside the scope of Article 28 EC. Advocate General Poiares Maduro in his opinion in Joined Cases C-158/04 and C-159/04 Alfa Vita Vassilopoulos and Carrefour-Marinopoulos was not in favor.
Sweden had a rule laying down that jet-skis could only be used on "general navigable waterways" and such other waterways as expressly permitted by local rules. As a matter of fact, no such local rules had been passed and consequently jet-skis could only be used on "general navigable waterways". But "general navigable waterways" are relatively few and very busy with commercial traffic. In practice, therefore, the actual use of jet-skis in Sweden are merely marginal.
The Court recalled its classic case-law according to which measures taken by a member State, the aim or effect of which is to treat goods coming from other member States less favorably and, in the absence of harmonisation of national legislation, which create obstacles to the free movement of goods by applying, to goods coming from other member States where they are lawfully manufactured and marketed, rules that lay down requirements to be met by such goods, even if those rules apply to all products alike, must be regarded as ‘measures having equivalent effect to quantitative restrictions on imports’ for the purposes of Article 28 EC (see to that effect, Case 120/78 Rewe-Zentral (Cassis de Dijon)  ECR 649, paragraphs 6, 14 and 15; Case C-368/95 Familiapress  ECR I-3689, paragraph 8; and Case C-322/01 Deutscher Apothekerverband  ECR I-14887, paragraph 67). Any other measure which hinders access of products originating in other member States to the market of a member State is also covered by that concept (Case C-110/05 Commission v. Italy , paragraph 37).
Even if the national regulations at issue do not have the aim or effect of treating goods coming from other member States less favorably, which is for the national court to ascertain, the restriction which they impose on the use of a product in the territory of a member State may, depending on its scope, have a considerable influence on the behaviour of consumers, which may, in turn, affect the access of that product to the market of that member State. Consumers, knowing that the use permitted by such regulations is very limited, have only a limited interest in buying that product (Case C-110/05 Commission v. Italy, paragraphs 56 and 57).
The Court continued that the Swedish measures could be justified under Article 30 EC but that it was for the national court to assess the facts of the case and determine whether the measures in question in fact met the requirements for such a justification.
It recalled that in preliminary reference proceedings - based on a clear separation of functions between the national courts and the Court of Justice - any assessment of the facts in the case is a matter for the national court (Case C-450/06 Varec  ECR I-581, paragraph 23). But to give the national court a useful answer, the Court may, in a spirit of cooperation with national courts, provide it with all the guidance that it deems necessary (Case C-49/07 MOTOE , paragraph 30).
The Court continued that in the main proceedings, the national regulations had been in force only for about three weeks at the material time. The fact that measures to implement those regulations had not been adopted at a time when those regulations had only just entered into force ought not necessarily to affect the proportionality of those regulations in so far as the competent authority may not have had the necessary time to prepare the measures in question, a matter which falls to be determined by the national court.
If the national court were to find that implementing measures were adopted within a reasonable time but after the material time of the events in the main proceedings and that those measures designate as navigable waters the waters in which the accused in the main proceedings used personal watercraft and consequently had proceedings brought against them, then, for the national regulations to remain proportionate and therefore justified in the light of the aim of protection of the environment, the accused would have to be allowed to rely on that designation; that is also dictated by the general principle of Community law of the retroactive application of the most favourable criminal law and the most lenient penalty (Joined Cases C-387/02, C-391/02 and C-403/02 Berlusconi and Others  ECR I-3565, paragraph 68).