The most recent developments regarding legal privilege relate to competition law infringements. The Spanish Competition Authorities have applied EU case law on attorney-client legal privilege, which is fairly well established and detailed. Effectively, the Spanish Competition Authorities have recognized that correspondence exchanged with an external lawyer who practices within the European Economic Area "for the purpose and the interests of the client's rights of defense" is covered by legal privilege. The protection of legal privilege also covers "internal memoranda which are confined to reporting the text or the content" of communications exchanged with external lawyers.

Although EU case law on attorney-client legal privilege has been applied by the Spanish Competition Authorities in the course of a competition law investigation, it is not clear whether the same principles will be applicable in a straightforward manner in the course of other kinds of investigations conducted by other authorities.

In relation to criminal matters, recent developments focus on the relationship between professional secrecy and attorney-client privileged communications when the client is imprisoned. In a recent Spanish case, an Examining Magistrate's Court authorized the interception of the defendants' communications whilst they were in jail, even where those communications were with their lawyers. The defendants' appeal was eventually upheld by the Criminal Court of the High Court of Justice of Madrid on the basis that, according to the Spanish Penitentiary Act, communications between a lawyer and a client, even when the client is imprisoned, are protected by professional secrecy. Judges may only intercept their communications if two requirements are satisfied: (i) the defendant is charged with an offense of terrorism; and (ii) the intervention is authorized by the Prison Authority and approved by the judge on the basis that it is necessary to ascertain the truth of the case.

The examining magistrate who authorized the interception of the communications of the imprisoned defendants was found guilty of a criminal offense by a judgment issued by the Spanish Supreme Court on 17 January 2012.