Legal AI

Efficiency vs. Hallucination

A recent ruling by the Guimarães Court of Appeal (Tribunal da Relação de Guimarães) has served as a major reality check for the Portuguese legal community. The court exposed the use of fake case law and non-existent doctrinal citations in a legal pleading, a clear case of AI hallucination. This incident, in which Generative AI 'invented' legal precedents that appeared authentic but were pure fiction, should not be viewed as an isolated professional error. Instead, it serves as a critical warning on how the legal sector is navigating digital transformation and the risks of relying on unverified LegalTech tools.

We are currently living in a technological 'arms race.' Law firms and legal departments are facing unprecedented pressure to boost productivity, slash response times, and manage volumes of information that are humanly impossible to process. This drive for legal efficiency is no longer a luxury but a necessity for survival in a data-driven market.

In this landscape, Generative AI tools emerge as the 'perfect partner.' However, the real risk lies in the shift from AI as a supportive tool to AI as the primary responsible for core legal functions. When the 'assistant' starts making essential decisions without human oversight, the line between legal efficiency and professional liability begins to blur.

When a lawyer abandons their role as curator and validator, technology shifts from being a strategic asset to a significant liability in terms of civil and ethical responsibility. Without human oversight, the very tools meant to ensure efficiency become a source of professional risk.

AI is not a search engine

One of the most frequent misconceptions is confusing Large Language Models (LLMs), such as ChatGPT, with search engines or official legal databases (like ITIJ). Generative AI does not 'search' for facts; it predicts the statistical probability of the next word in a sentence. It prioritizes linguistic coherence over factual accuracy.

When asked for a ruling on a specific matter, AI can construct a response with an impeccable structure: a plausible case number, real judges' names, and a legally coherent summary—even if the document never existed. This is the phenomenon of 'AI hallucination.' In a legal context, this can be interpreted as bad faith litigation and a violation of the duty of truth (or duty of candor) toward the court.

The Irreplaceable Role of the Legal Professional

As highlighted by the Guimarães Court of Appeal, courtrooms are places of 'attentive human minds.' Law goes far beyond the mechanical application of rules; it is an exercise in interpretation, ethics, and social commitment. Therefore, the use of Generative AI in legal pleadings requires a strict Human Verification Protocol:

1. Primary Source Citation: It is imperative that the legal professional consults the official source to verify the existence and validity of any ruling or statute before citing it. Relying on AI-generated summaries without verifying the original text is a risk to professional integrity.
   
2. Intellectual Responsibility: AI may generate the draft, but the signature at the end of the document belongs to the lawyer. This signature ensures that the content has been thoroughly reviewed, understood, and approved. It serves as a guarantee that the professional takes full ownership of the legal arguments presented.
   
3. Transparency: The debate over the need to disclose the use of AI tools in court is gaining momentum, to safeguard legal certainty and maintain public trust in judicial institutions.

Artificial Intelligence is a permanent presence and will play a crucial role in the democratization and streamlining of justice. However, its implementation requires a new kind of AI literacy. The Guimarães case should not discourage lawyers from using technology, but rather incentivize them to master it with greater rigor.

The future of Law will not be 'Human vs. Machine,' but rather 'Human with Machine, a symbiotic relationship, provided that the professional remembers that technical rigor and integrity cannot be automated. AI can be an excellent assistant, but it will never be the lead counsel.