The ECJ has furthermore been wary of the objection that to answer a reference would be to apply rather than interpret the relevant law.
In fact the ECJ is usually willing to give v detailed answers e.g. Problem of current system is that courts are overloaded with cases and this delays justice (especially answer of national court while waiting for a reference).
ECJ was initially very liberal about answering references: It would correct improperly framed references (see Schwarze C-16/65) and didn't worry about the reasons for which a reference was made nor the facts on which it was based (See Simmenthal).
ECJ regards itself as having ultimate authority to decide whether a reference is warranted or not (See Foglia 1).
(2) Where such a question is raised before any court or tribunal of a Member State, that court or tribunal may, if it considers that a decision on the question is necessary to enable it to give judgment, request the Court of Justice to give a ruling thereon.
(3) Where any such question is raised in a case pending before a court or tribunal of a Member State against whose decisions there is no judicial remedy under national law, that court or tribunal shall bring the matter before the Court of Justice.' * * * * * NB ECJ decisions under art 234 are referential: They are not a final ruling (the right to make one is reserved to national courts) and ECJ is NOT an appellate court.
TUTORIAL 3: THE RELATIONSHIP BETWEEN EC LAW AND NATIONAL LAW: PRELIMINARY REFERENCES; DIRECT EFFECT, INDIRECT EFFECT AND INCIDENTAL EFFECT 1.
Preliminary References on the Interpretation of Community law and the validity of Community acts Craig & de Burca Ch. 234 EC: (1) 'The Court of Justice shall have jurisdiction to give preliminary rulings concerning: (a)the interpretation of this Treaty; (b) the validity and interpretation of acts of the institutions of the Community and of the ECB; (c) the interpretation of the statutes of bodies established by an act of the Council, where those statutes so provide.
ECJ's ruling delivered to a particular court and available on request).
In fact it's become more vertical (ECJ superior to national courts) and multilateral (treating ECJ references to a particular court as general precedents).