El impacto de la inteligencia artificial generativa en la lex artis del abogado

The incorporation of generative artificial intelligence systems into legal practice raises significant questions regarding lawyers’ duty of professional diligence and the liability arising from their use. This paper examines the impact of these tools on the configuration of the lawyer’s lex artis, taking as its starting point for the analysi the case decided by Order No. 2/2024 of the High Court of Justice of Navarre, dated 4 September 2024, while also considering subsequent case law, in particular Judgment No. 2408/2026 of the High Court of Justice of Galicia, dated 26 May 2026, as. well as the applicable regulatory and ethical framework. Drawing on the analysis of the General Statute of the Spanish Legal Profession, the Code of Conduct of the Spanish Legal Profession, Interpretative Circular 3/2026, and Regulation (EU) 2024/1689, the study explores the duties of supervision, verification and validation required of lawyers when using generative artificial intelligence systems, as well as the potential disciplinary and civil liability arising from their negligent use. The paper concludes that generative artificial intelligence does not alter the traditional foundations of lawyers’ professional liability. However, it reinforces the requirements of diligence, control and human oversight, which are progressively becoming integrated into the standards that define professional conduct in accordance with the lawyer’s lex artis.