AG Bot argued that this should be considered a measure equivalent to a quantitative restriction on trade, that required justification.

It should be recalled that, according to settled case-law, all trading rules enacted by Member States which are capable of hindering, directly or indirectly, actually or potentially, intra-Community trade are to be considered as measures having an effect equivalent to quantitative restrictions and are, on that basis, prohibited by Article 28 EC (see, in particular, Dassonville, paragraph 5).

It is also apparent from settled case-law that Article 28 EC reflects the obligation to respect the principles of non-discrimination and of mutual recognition of products lawfully manufactured and marketed in other Member States, as well as the principle of ensuring free access of Community products to national markets (see, to that effect, Case 174/82 Sandoz [1983] ECR 2445, paragraph 26; Case 120/78 Rewe‑Zentral (Cassis de Dijon) [1979] ECR 649, paragraphs 6, 14 and 15; and Keck and Mithouard, paragraphs 16 and 17).

Hence, in the absence of harmonisation of national legislation, obstacles to the free movement of goods which are the consequence of 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 constitute measures of equivalent effect to quantitative restrictions even if those rules apply to all products alike (see, to that effect, Cassis de Dijon, paragraphs 6, 14 and 15; Case C‑368/95 Familiapress [1997] ECR I-3689, paragraph 8; and Case C‑322/01 Deutscher Apothekerverband [2003] ECR I-14887, paragraph 67).

The Commission's action must therefore be dismissed in so far as it concerns trailers which are not specially designed to be towed by motorcycles and are legally produced and marketed in Member States other than the Italian Republic.

Secondly, the failure to fulfil obligations alleged by the Commission in regard to trailers which are specially designed to be towed by motorcycles and are legally produced and marketed in Member States other than the Italian Republic remains to be examined.

Thus, Article 56 of the Highway Code prevents a demand from existing in the market at issue for such trailers and therefore hinders their importation.

It follows that the prohibition laid down in Article 56 of the Highway Code, to the extent that its effect is to hinder access to the Italian market for trailers which are specially designed for motorcycles and are lawfully produced and marketed in Member States other than the Italian Republic, constitutes a measure having equivalent effect to quantitative restrictions on imports within the meaning of Article 28 EC, unless it can be justified objectively.

[1] Italian Trailers held that laying down requirements to be met by goods can constitute measures having equivalent effect to quantitative restrictions if they present an obstacle to their free movement, even if those rules apply to all products alike, demonstrating an excessively broad scope for what will constitute a measure equaling equivalent effect to a quantitative restriction.