In a medical malpractice and/or medical error case, proof is always one of the main ‘obstacles’ to the successful outcome of a lawsuit of this nature, since it is up to the plaintiff (patient) to guarantee the production of evidence regarding this error. Although each legal case has its own idiosyncrasies (namely whether the case is brought against a private or public health organisation), we must emphasise that the burden of proof for medical error always falls on the patient who allegedly suffered an incorrectly performed medical act.

In this regard, on 27.03.2025, the Portuguese Supreme Administrative Court handed down Ruling 5/2025 on this matter, the summary of which is peremptory in admitting that ‘In a civil liability action for medical acts carried out in an SNS unit, under Law 67/2007, it is up to the plaintiff to allege and prove the assumptions of non-contractual civil liability: fact, unlawfulness, fault, damage and causal link. (…)’.

Therefore, in cases of medical error in which non-contractual civil liability is at issue, namely based on acts under the protection of Law 67/2007, there can be no doubt that it is the plaintiff who must bring to court all the evidence necessary to prove the various requirements of this liability, namely unlawfulness and fault. And with regard to these requirements in particular, the aforementioned judgement clarifies that “unlawfulness, under the terms of article 9, paragraph 1 of the RRCEE [Regime da Responsabilidade Civil Extracontratual do Estado e Demais Entidades Públicas, our inclusion], covers not only the violation of legal norms, but also the failure to comply with technical rules or objective duties of care. In the case of medical error, this unlawfulness results from failure to comply with the leges artis, measured according to the state of medical science at the time of the acts carried out, and the doctor’s obligation is one of means and not of result. Fault is measured by the standard of diligence required of a zealous professional, under the terms of article 10 of the RRCEE”. Therefore, in the event of a lawsuit of this type, we must be clear that the preparation of these processes is essential, and the plaintiff must equip himself with all the elements necessary to produce that evidence, namely by obtaining a copy of the entire clinical file and, preferably, an opinion drawn up by a specialist in the area of medicine in question, who assesses the clinical file against the medical guidelines protocolised for the medical act under evaluation. In addition to the aforementioned opinion, the plaintiff must ensure that it is possible to include in the witness list a specialist in the area of medicine in question who can attest to the incorrectness of the medical act, in order to prove the requirements of unlawfulness and fault mentioned above.

In view of all the above and taking into account the position of doctrine and case law on this matter, we recommend that you prepare the matter from the out-of-court phase with lawyers with experience in this area of practice, who can advise you correctly on the case. Belzuz Advogados S.L.P. – Sucursal em Portugal has a team of lawyers with extensive experience in litigation and, in particular, medical liability, who can provide this legal advice.