AI rules for lawyers, by country · Costa Rica · Latin America

Costa Rica: the lawyer who signs states when AI was consulted

Tribunal Segundo de Apelación Civil de San José, Voto 365-2026 (29 June 2026) · Tribunal Agrario, Segundo Circuito Judicial de San José, Voto 874-2026 (28 August 2026)

Two decisions read in full, in Spanish. Translations are ours; the Spanish original follows each quotation.

Costa Rica has no court rule on lawyers using AI. Two of its appeal courts have answered the question in decided cases instead. In June 2026 the Second Civil Appeal Tribunal of San José found an appeal that appeared to be built with the help of AI, relying on a repealed article and on judgment numbers that did not match their content or did not exist, and directed that in future the lawyer who authenticates the filing checks the material and, where these tools are used, states that AI was consulted. In August 2026 the Agrarian Tribunal found that precedents attributed to it did not correspond at all to the issues in the case. Neither imposed a penalty.

The two decisions

29 Jun 2026Second Civil Appeal Tribunal of San José, Second Section, Voto 365-2026, Expediente 24-000710-0217-CI, Judge Osvaldo López Mora sitting alone. The appeal relied on article 221 of the repealed Civil Procedure Code (Law 7130) and cited judgments numbered 421-F-2018 and 1012-2019, attributed to the same tribunal, that do not correspond to their stated content or do not exist. The judgment otherwise went largely for the claimant.
28 Aug 2026Agrarian Tribunal, Second Judicial Circuit of San José, Voto 874-2026, Expediente 25-000101-1129-AG, a bench of three judges. The precedents attributed to the tribunal did not concern felling a tree or acquiescence, the issues before it. The judgment below was confirmed.

What the courts said

The Second Civil Appeal Tribunal did not prohibit AI. It asked for responsibility and for candour:

“Certainly the appeal appears to have been built with the help of an artificial intelligence which, although not prohibited, must be used responsibly, and it is recommended that the legal professional say so, as a matter of professional ethics and transparency.” “Ciertamente el mismo parece ser construido con la ayuda de una inteligencia artificial, lo cual, si bien no es prohibido, en caso de utilizarse debe hacerse con responsabilidad y se recomienda así se indique por parte del profesional en derecho, ello desde la ética profesional y transparencia.”

Then it gave a direction for the future, addressed to the lawyer who authenticates the filing:

“In future, the legal professional who authenticates the filing must check and attend to the irregularities detected, stating, where these valuable support tools are used, that some form of artificial intelligence has in fact been consulted.” “en lo sucesivo, deberá el profesional en derecho autenticante del memorial, corroborar y prestar atención a las irregularidades detectadas, señalando en caso de utilizar estas valiosas herramientas de apoyo, que efectivamente ha procedido a consultar algún tipo de inteligencia artificial.”

Two months later the Agrarian Tribunal, on precedents attributed to it that did not fit the case:

“That inconsistency suggests that the claimant or appellant may have resorted to the negligent or imprecise use of artificial intelligence tools to generate citations that do not exist or do not bear on the case.” “Tal inconsistencia sugiere que la parte actora o recurrente pudo haber recurrido al uso negligente o impreciso de herramientas de inteligencia artificial para generar citas inexistentes o impertinentes al caso.”

Why Costa Rica matters

A disclosure duty usually comes from a rule committee. Here it came from an appeal judge, in a published judgment, addressed to the lawyer whose name authenticates the filing. The question it asks is the one every court on this site is converging on: who checked the work, and can they show it?

What to do about it

The court asked the lawyer to say when AI was consulted. A record shows it.

A statement says AI was consulted and the material was checked. A signed, tamper-evident record creates checkable evidence of who approved the exact words and when, sealed to the document that was filed, and checkable by the other side or the court without trusting the person who made it.

Regulayer™ for attorneysVerify a record free →

Sources

Tribunal Segundo de Apelación Civil de San José, Voto 365-2026, 29 June 2026, read in full
Tribunal Agrario, Segundo Circuito Judicial de San José, Voto 874-2026, 28 August 2026, read in full
Each is a print of the decision as published in the Costa Rican judiciary’s Nexus database, from the AI Hallucination Cases document store.

Read in full at the two decisions. Translations are ours. Information, not legal advice, and not advice on Costa Rican law.

Information, not legal advice, and not advice on the law of any jurisdiction. Every entry is verified against the issuing body’s own document; where a source is reporting rather than the document, we say so.