Opinion Of Mr Advocate General Capotorti

Mr President,

Members of the Court,

1. This Court has recently had occasion to consider and to answer some questions of interpretation of Community law raised by national courts in relation to the reimbursement of charges unduly paid by private citizens, which were imposed by municipal rules of law contrary to the EEC Treaty. I refer, in particular, to the two judgments of 27 February 1980 in Case 68/79, Hans Just [1980] ECR and of 27 March 1980 in Case 61/79, Amministrazione delle Finanze ν Denkavit Italiana [1980] ECR. This case, however, originates in a claim for restitution of monies which the Intervention Board for Agricultural Produce (which is the British authority charged with managing the agricultural policy of the EEC in the United Kingdom) collected from private citizens by duly applying Community rules, the validity of which is now disputed following upon an preliminary ruling delivered by this Court.

2. In regard to the first question, it is appropriate to recall at the outset that in the Milac judgment of 3 May 1978 the Court held Article 1 of Regulation No 539/75 of the Commission to be invalid because it was contrary to the basic regulation, No 974/71 of the Council. In fact, Article 1 (2) (b) of the latter regulation authorized the introduction of monetary compensatory amounts only for products the price of which depends on that of products for which intervention arrangements have been provided. In the case of powdered whey, since it is a product to which intervention measures do not apply, it would have been necessary — in order to make lawful the introduction of monetary compensatory amounts — that its price be dependent upon that of skimmed-milk powder. The Court, however, held that no such dependence existed. It may therefore be said that the invalidity of the said provision of Regulation No 539/75 was a consequence of the fact that the price of skimmed-milk powder has no effect upon the price of powdered whey.

3. The second question submitted for a preliminary ruling is concerned with whether a duty to make repayment is incumbent upon national bodies which have levied monetary compensatory amounts on the basis of Community rules subsequently declared invalid, and if so , with the scope of that duty.

4. I mentioned at the outset the judgments of 27 February 1980 in Case 68/79, Just and 27 March 1980 in Case 61/79, Amministrazione delle Finanze ν Denkavit Italiana, and I observed that in those cases the question of repayment was tackled starting from a very different situation, namely the fact that the charges unduly paid had been imposed on individuals by the Member States in contravention of Community rules. That notwithstanding, it is possible to extract from both of the judgments matters which assist in the solution of the present case.

5. Making reference to national law to determine the detailed conditions for recovery of undue payment — undue payment in the sense just now clarified — certainly does nót represent the most fair or convenient solution. Both in the Ferwerda judgment (already cited) and in that delivered on 27 March 1980 in Joined Cases 66, 127 and 128/79, Amministrazione delle Finanze v Società Meridionale Industria Salumi [1980] ECR, the Court had occasion to observe that, whilst the system relating to the levying of financial charges of Community origin is dominated by the general principle of equality, we are, on the other hand, only at the start of the path which will lead to achieving nondiscrimination between all Community traders in regard to the conditions of form and substance governing claims for recovery of undue payment. At the present time, given the differences in legal rules between one Member State and another, that inequality in treatment exists. The Council is exercising its power to regulate matters with lamentable slowness. In fact, only last year did Regulation No 1430/79 of 2 July 1979 introduce rules of this kind on reimbursement of import and export duties. The rules will come into force on 1 July next. That partial and restricted step is certainly not sufficient to correct the absurdities arising from the differences in the conditions laid down by national laws. I refer in particular to the well-known problem of limitation periods. However, it was stressed in the same judgments of 5 March 1980 in Case 265/78, Ferwerda and of 27 March 1980 in Joined Cases 66, 127 and 128/79, Amministrazione delle Finanze ν Società Meridionale Industria Salumi that the necessarily technical and detailed nature of such provisions means that a judicial interpretation can only provide a partial remedy.

6. It remains to consider the question of interest on the sums the repayment of which is claimed, which is the subject of the third request for a preliminary ruling. In this context I would recall that, in his opinion in the Roquette Frères case which I have already cited, Mr Advocate General Trabucchi had occasion to state that payment of the interest on a capital sum unduly paid is strictly dependent upon the right to repayment of the principle itself. The determination of the amount due as interest on a contract or as default interest directly and necessarily depends on the amount of the sum unduly paid and on the period which has elapsed between the undue payment, or at least the final notice served by the body collecting the payment, and its repayment. ... An application for interest is subject to the same criteria as those laid down by the case-law of the Court in respect of the claim for repayment of the capital on which the interest is based. An application for interest must, therefore, be made in accordance with the same procedure as that applicable to recovery of the capital sum. The Court decided to that effect in its judgment in that case on 21 May 1976 by stating (at paragraph 12 of the decision) that in the absence of provisions of Community law on this point, it is currently for the national authorities, in the case of reimbursement of dues improperly collected, to settle all ancillary questions relating to such reimbursement, such as any payment of interest. In my opinion, the answer to the question here under consideration must be strictly in accordance with that precedent.

7. For the reasons set out above I conclude by suggesting that the Court answer as follows the questions submitted for a preliminary ruling by the High Court of Justice, London, by order of 23 July 1979:

1 Translated from the Italian.