In Dubio Pro Operario After Argentina’s Labor Reform

The Argentine labor-law rule known as in dubio pro operario has not disappeared entirely, but it is no longer stated as broadly in Section 9 of the Employment Contract Act. Law 27,802 retained the rule used to choose the provision that is more favorable to the employee when competing legal or collective-bargaining rules may apply. It removed the express instruction to decide in the employee’s favor when doubt concerns the interpretation of the law or the assessment of evidence. Whether those two protections survive through constitutional law, human-rights treaties and general labor-law principles will have to be settled by the courts.

What does in dubio pro operario mean?

The Latin phrase broadly means that an unavoidable doubt should be resolved in favor of the employee. It derives from the protective principle that structures Argentine employment law: the employer normally organizes the business, controls documentation and holds greater economic and bargaining power, while the employee performs work within that organization.

That idea never meant that an employee could win without evidence, that a court could disregard the wording of a statute or that every disagreement qualified as legal doubt. It operated as a final criterion after identifying the governing rules, applying ordinary methods of interpretation and assessing the available evidence. This limited role is important for foreign companies because the phrase is often translated too broadly.

A three-stage history: 2008, 2023 and 2026

In 2008, Law 26,428 amended Section 9. It expressly directed judges and other decision-makers to choose the interpretation most favorable to the employee when an unavoidable doubt concerned the meaning or scope of the law or the assessment of evidence. This website’s original Spanish article, published in 2009, explained that amendment.

In December 2023, Emergency Decree 70/2023 attempted to retain the rule while adding conditions. It referred to the exhaustion of investigative measures, an insurmountable evidentiary doubt, procedural consistency, due process and the general rule that a party must prove the facts it alleges. Irrespective of the litigation that affected the decree, its wording shows an effort to restrict rather than simply erase the evidentiary dimension.

Law 27,802 adopted a different technique in 2026. Section 3 replaced Section 9 in full and retained only a paragraph about the more favorable rule. It omitted the former provisions concerning statutory interpretation and evidence. The reform therefore changed the substance of the section, not merely its terminology.

Three legal questions that should not be confused

First, choosing the more favorable rule. The same employment-law institution may be regulated by the Employment Contract Act, a special statute and a collective bargaining agreement. Current Section 9 expressly requires the more favorable body of rules to prevail, using an institution-by-institution comparison. A party may not ordinarily select isolated fragments from different regimes to manufacture a new and uniquely favorable arrangement.

Second, interpreting an ambiguous rule. Here there are not two competing sources. One applicable provision reasonably supports more than one interpretation. The former text told the decision-maker to prefer the employee-favorable interpretation after ordinary methods failed to remove the doubt. Law 27,802 deleted that instruction from Section 9.

Third, assessing uncertain facts. The legal text may be clear while the historical facts remain disputed: how many hours were worked, whether an instruction was given, whether a notice was received or whether a payment covered a particular item. The former version projected favorability onto an insurmountable evidentiary doubt. It did not exempt the employee from evidentiary burdens or turn an unsupported allegation into proof.

What current Section 9 expressly retains

The official text of Law 27,802 labels Section 9 “The principle of the rule most favorable to the employee.” When doubt concerns the application of legal or collective-bargaining provisions, the more favorable one prevails, assessed under the grouping-by-institutions method. The continued statutory force of that test is clear.

The dispute concerns what Congress omitted. By replacing the entire section and retaining only one of the three former rules, the legislature signaled a restrictive intent that must be taken seriously. The open question is whether that choice is sufficient to exclude every application of the principle when constitutional or treaty-based grounds are invoked.

Legislative intent and the question that remains open

The starting point should be the language chosen by Congress. Law 27,802 replaced Section 9 in full, expressly retained the more-favorable-rule test and omitted the directives on interpretation and evaluation of evidence. That selection is difficult to dismiss as accidental. It is strong evidence that the legislature intended to narrow the role that the principle previously played within the Employment Contract Act.

Recognizing that intent does not, by itself, end the constitutional inquiry. Section 14 bis of the Argentine Constitution, human-rights treaties and the legal system’s integration rules remain applicable. New Section 11 of the Employment Contract Act refers unresolved issues to the general principles of employment law, equity and good faith. Section 2 of the Civil and Commercial Code also requires interpretation consistent with the Constitution, human-rights treaties and legal values.

Those sources do not automatically restore the paragraphs Congress removed. A party arguing that in dubio pro operario survives must identify the superior right at stake, the precise doubt in the case and why the proposed constitutional solution should prevail despite the legislative choice. The opposing position may rely on the deliberate omission and the need to respect the statute’s new structure. That tension—not an assumed answer—is the issue courts will have to decide.

Within this debate, Guillermo Unzaga Domínguez argues for continuity through Argentina’s constitutional and treaty framework and the integration of the legal system. His chapter “La vigencia del in dubio pro operario frente a la reforma legislativa,” in Nuevos aportes críticos de la reforma laboral. Ley 27.802, Labor Dossier No. 12, pages 45-53, offers a relevant scholarly position. It is neither the exclusive basis of this article nor settled case law.

Procedural rules may affect the outcome

The Employment Contract Act is national substantive law, while each jurisdiction applies its own procedural rules. Burdens of proof, statutory presumptions, judicial powers and methods of evaluating evidence may influence how a dispute is developed and decided. Those tools should be applied before a court concludes that a residual doubt exists.

Similar disputes may therefore follow different paths depending on the applicable procedure and the evidence actually produced. Procedural rules do not automatically restore the deleted language or override a superior guarantee, but they may determine when the debate about doubt becomes relevant.

What the reform did not change

Removing two paragraphs from Section 9 did not erase every evidentiary presumption contained elsewhere in labor legislation. It also did not shift every burden of proof to the employee or permit courts to decide without reasons. Due process, procedural consistency, local evidence rules and the duty to explain how the record supports the judgment all remain relevant.

Favorability is also different from curing a complete absence of proof. When a fact had to be established and no evidence supports it, the problem may be failure of proof rather than a genuine residual doubt. The line between insufficient evidence and an insurmountable doubt has always been difficult. The new wording makes that classification even more consequential.

Two practical examples

Example 1: a variable commission. A collective bargaining agreement and a company policy may regulate the calculation base differently. The first question is which sources govern that institution and which body of rules is more favorable; current Section 9 expressly addresses that conflict. If the applicable company policy itself contains an ambiguous phrase, the employee-favorable interpretation is no longer expressly stated in Section 9 and must be argued through other interpretive rules.

Example 2: overtime. An employee claims to have worked two hours beyond the recorded schedule, while the employer denies it. Access logs, messages, timekeeping systems, witnesses and supervisory records may support either account. The court must assess the record under local procedure. Removing evidentiary doubt from Section 9 does not automatically make missing employer records irrelevant, because other presumptions and documentation duties may apply. Nor does it turn an unsupported statement into sufficient evidence.

What companies operating in Argentina should do

The riskiest reading for an employer is to assume that the reform makes documentation less important. The opposite is true: when the statutory tie-breaking rule becomes less explicit, a clear factual record becomes more valuable. Companies should review personnel files, payslips, timekeeping, variable-compensation policies, leave communications, disciplinary notices and proof of delivery.

Records should be created when events occur, not reconstructed after a formal demand arrives. A spreadsheet completed months later or an email with no proof of receipt is weaker than a simple process applied consistently. Our guide to annual leave after Argentina’s labor reform illustrates the value of clear notice, consent when required and reliable records.

Before dismissal, a significant disciplinary measure or a response to an employee’s formal notice, separate three questions: which rule applies, which interpretation is defensible and which facts can be proved. Combining them usually produces rushed decisions. Foreign companies building their first local team should incorporate this discipline into the broader compliance process described in our guide on how to hire your first employee in Argentina.

What employees should preserve

For employees, the reform does not mean that a legitimate claim has lost every protective foundation. It does make it more important to preserve payslips, lawful messages, schedules, emails, certificates and other materials showing the real working conditions. Legal advice should ideally be obtained before sending a formal demand, refusing an instruction or treating the employment relationship as terminated, because the wording and timing of communications may affect the later dispute.

A debate that the courts must develop

Law 27,802 is recent. Future judgments will have to determine whether the legislative deletion prevents the use of interpretive and evidentiary favorability, whether those rules survive through constitutional or treaty law, and the conditions under which they may be invoked. Courts must also distinguish employee-favorable interpretation from ordinary evidence rules so that neither formal neutrality nor automatic favorability replaces reasoned adjudication.

For now, the sound conclusion has two parts: the more favorable rule remains expressly in force, and the deletion of the other two directives reflects a legislative decision to restrict Section 9. Any continued role for interpretive or evidentiary favorability is a constitutional argument that must be raised and decided in the individual case, not an effect that should be assumed.

Frequently asked questions

Did Law 27,802 eliminate every employee-favorable rule?
No. Section 9 expressly retains the more-favorable-rule test when legal or collective-bargaining provisions compete.

Must an Argentine judge still interpret every doubt for the employee?
Section 9 no longer says so expressly. A constitutional and treaty-based argument supports continuity, but the issue must be litigated and decided in context.

Does evidentiary doubt allow an employee to win without proof?
No. Evidentiary burdens, statutory presumptions and local procedural rules apply first. An insurmountable doubt is different from a complete absence of supporting evidence.

Are the more favorable rule and in dubio pro operario identical?
Not precisely. One selects between competing rules; the latter, in its strict sense, guides the interpretation of an ambiguous applicable rule.

Can procedural rules affect the outcome?
Yes. Burdens of proof, statutory presumptions and judicial powers depend on the applicable system and must be examined before a residual doubt is found.