Spain joined the Schengen Convention now part of the EU acquis on 25 June 1991. In that context it is up to Spain to indicate which national officers and authorities can make use of legal instruments in areas such as cross border police cooperation (Article 39), cross border surveillance (Article 40) and hot pursuit (Article 41).

Similarly, Article 101(4) of the Schengen Convention obliges each Contracting Party to indicate the list of competent authorities which are authorised to search the data contained in the Schengen Information System (SIS) directly.

Therefore, including the Basque Country's autonomous police force in Spain's protocol to the Schengen Agreement is a national competence and the Commission has no say on this matter.