In corso di pubblicazione su Questione Giustizia 2013, n. 4.

The paper analyses the Italian Constitutional Court judgment no. 231/2013 with regard to the legal interpretation method. After describing the new legal criterion to establish company trade unions, the A. take sides in the debate that pits the formal rationality of the literal interpretation of a law rule to practical rationality of constitutional interpretation of justice. 
The A. agrees with the judgment of Constitutional Court for two reasons: first of all, on the method, because he believes that the constitutional jurisprudence can legitimately manipulate the content of an ordinary rule of law if it need to respect the Constitution. Secondly, the A. agrees with the judgment because the criterion of interpretation based on the practical rationality allows to respect the founding principles of the Italian Constitution, which is the industrial democracy, that implement the equality in collective economic relations.