Judicial review of public law decisions in Argentina is governed by the principle of legality and a dual system of norms. At the federal level, the National Administrative Procedures Act (Law 19.549) establishes the general framework, while each province and the City of Buenos Aires apply their own local procedural codes.

Specific regimes coexist for highly regulated sectors, such as energy, public utilities and customs law, which often require exhausting specialised administrative remedies before regulatory bodies or specialised tribunals prior to seeking judicial review. Regardless of the regime, all administrative actions remain subject to constitutional standards of effective judicial protection.

The competent forum for judicial review in Argentina is determined by the federal or local nature of the parties and the subject matter. Challenges against the National State or its agencies are heard by the Federal Administrative Courts (Justicia Nacional en lo Contencioso Administrativo Federal), where jurisdiction is primarily established when a national entity is a party to the litigation.

Disputes involving local administrative acts or provincial regulations fall under the exclusive jurisdiction of the administrative courts of each province or the City of Buenos Aires.

In Argentina, susceptibility to judicial review is primarily determined by the legality of the administrative decision. The central mechanism for challenge is the action for annulment (acción de nulidad), which focuses on whether the decision complies with all essential legal requirements. This review evaluates the act’s validity – specifically elements such as purpose, cause, motivation and procedure – to ensure it aligns with the applicable legal framework. For a decision to be susceptible to challenge, it must be a final act that produces direct legal effects on the rights or legitimate interests of the claimant.

In Argentina, primary legislation can be challenged through a judicial review of constitutionality. This process ensures that laws enacted by Congress or local legislatures align with the National Constitution and, where applicable, provincial constitutions. Argentina employs a “diffuse” control system, meaning that any judge across all jurisdictions has the authority to declare a law unconstitutional within the context of a specific legal dispute.

Challenges are typically brought through a direct action for unconstitutionality (acción declarativa de inconstitucionality) or as a defence within an action for annulment against a specific act of application. The grounds for such challenges usually involve the violation of fundamental rights, the breach of the hierarchy of norms, or the lack of proportionality in the legislation.

Secondary legislation, such as executive decrees and administrative regulations, can be challenged in Argentina through actions for annulment or declarations of unconstitutionality. These provisions are subject to judicial review if they violate the hierarchy of norms, particularly when they exceed the scope of the law they intend to implement or fail to comply with the essential requirements for administrative acts. The judiciary evaluates these regulations to ensure their reasonableness and legality, whether through a direct judicial action or as a defence in a specific case.

It is possible to challenge government decisions that affect a single individual, known as “particular administrative acts” (actos administrativos de alcance particular). These decisions are challenged through an action for annulment (acción de nulidad) whenever they infringe upon the subjective rights or legitimate interests of the claimant. For such a challenge to be admissible, the decision must be a final act that exhausts all available administrative remedies, subject to specific exceptions provided by law.

The judicial review of these individual decisions focuses on verifying that the act complies with all essential legal requirements, such as competence, cause, object and motivation. If the court finds the act to be unlawful, it will declare its nullity.

Agreements between public bodies and private entities, including both administrative contracts and those governed by private law, can be challenged before the judiciary. In Argentina, the judicial review of such agreements or the actions taken under them generally requires the prior exhaustion of administrative remedies, as prescribed by law.

The challenge is typically brought through an action for annulment or a claim for breach of contract, depending on whether the dispute concerns the validity of the administrative acts related to the agreement or its performance.

It is not possible to challenge acts that do not produce direct legal effects outside the Public Administration. Preparatory acts, internal reports and non-binding guidance are excluded from judicial review, as they do not constitute a final determination of the administration’s will. These actions are considered intermediate steps within an administrative procedure and do not independently affect the rights or legitimate interests of individuals. A challenge can only be brought against the final act that incorporates these preliminary steps or when a preparatory act effectively prevents the continuation of the proceedings.

In Argentina, judicial review is determined by the nature of the function exercised rather than the institutional nature of the entity. Consequently, it is possible to challenge decisions made by bodies that perform commercial or non-governmental activities, provided they are exercising “administrative functions” delegated by the State.

This applies to two main categories.

• Publicly owned corporations: decisions made by State-owned enterprises are subject to review when such enterprises act within the sphere of public law or exercise authority beyond mere commercial transactions.
• Non-governmental public entities: professional associations (Colegios Profesionales) or other entities that perform delegated public duties can be challenged when their decisions affect the rights of individuals in the exercise of those public functions.

The challenge follows the same principles as those against the Public Administration, provided that the action involves the exercise of public power (poder público).

In Argentina, the jurisdiction of Administrative Law Courts can be ousted by legislation or contract in specific cases, primarily through arbitration or choice-of-forum clauses.

• Arbitration: current regulations, such as those for public-private partnerships (PPPs) and specific administrative contracts, allow the State to submit disputes to binding arbitration. This effectively removes the matter from the ordinary judicial administrative sphere, provided the dispute concerns disposable economic rights.
• Choice of forum: in international contracts, especially those involving public credit or external financing, the law may authorise the Executive Branch to agree to the jurisdiction of foreign courts or international tribunals (prórroga de jurisdicción).

However, such ousters are limited to matters of a commercial or patrimonial nature. The core validity of administrative acts and constitutional challenges remain subject to the non-waivable oversight of the Argentine judiciary.

In Argentina, claimants must demonstrate that the administrative decision affects a legally protected interest (interés jurídico tutelado) in order to have standing. This concept encompasses both individual and collective rights, provided that the claimant can prove the existence of a “case”, “cause” or “controversy” (caso, causa o controversia).

The existence of a concrete dispute is an essential constitutional requirement for judicial intervention. Consequently, it is indispensable for the claimant to provide a well-founded allegation showing how the challenged illegality specifically impacts their interests. A “simple interest” (interés simple) – defined as a mere desire for the abstract observance of the law – is insufficient to grant standing. Therefore, judicial review is only available when there is a personal, certain and current grievance that requires judicial protection.

Charities and NGOs have extraordinary standing to challenge government decisions in defence of collective interests, even if they are not personally affected by the act. Under Article 43 of the National Constitution, registered associations that promote the protection of the environment, consumer rights, competition or general collective interests are expressly authorised to bring such challenges.

For this standing to be recognised, the following requirements must be met.

• Institutional purpose: the objectives stated in the association’s by-laws must have a direct relationship with the subject matter of the legal action.
• Collective grievance: the association must demonstrate how the challenged act specifically impacts the collective interests it represents, proving the existence of a “case” or “controversy”.
• Adequate representation: in cases involving “homogeneous individual rights” (such as patrimonial claims of consumers), associations are recognised as having adequate collective representation when a single event affects a plurality of individuals.

This legal framework ensures that collective rights are not left unprotected due to the lack of an individual claimant, provided the association does not seek the mere abstract control of legality.

It is possible for a person or entity to join an existing challenge against a government body through the mechanism of third-party intervention (intervención de terceros). Under Argentine procedural law, any party demonstrating a legally protected interest that could be affected by the court’s final ruling may request to intervene in the proceedings.

The process requires a formal petition to be filed before the court, justifying the intervenor’s standing and explaining the specific impact the case’s outcome would have on their legal sphere. In collective processes, associations often join as co-litigants to ensure adequate representation of the affected group.

Other parties may participate in administrative proceedings in various capacities, depending on the nature of their interest.

• Co-litigants (Litisconsortes) share a common legal position or factual cause with the original claimant and hold full party status, enabling them to produce evidence, file pleadings, and appeal rulings independently.
• Intervenors (Terceros) play an auxiliary role, supporting either the claimant’s or the administration’s position to protect their own related interests from the effects of the final judgment.
• Amicus curiae: NGOs or specialists may provide technical or legal opinions in cases of significant public interest. Their role is non-adversarial and limited to assisting the court without becoming a formal party to the litigation.
• Public entities: bodies such as the Public Defender’s Office (Defensor del Pueblo) or the Public Prosecutor’s Office (Ministerio Público) may intervene to guarantee the protection of collective rights or the general observance of the law.

In Argentina, there is no system of automatic disclosure or discovery as understood in common law jurisdictions. Instead, the evidentiary process is governed by the principle of party presentation, where each party must offer and produce the evidence that supports its claims during the corresponding procedural stage.

However, in administrative litigation, there is a specific and mandatory requirement for the government body to provide the court with the complete administrative record (expediente administrativo) related to the challenged decision. This record serves as a fundamental source of evidence and must be submitted by the administration upon the court’s request, usually at the beginning of the legal action. The failure of the administration to provide the full record can lead to a presumption in favour of the claimant’s factual allegations. Beyond this, any other documents or evidence must be specifically requested or offered by the parties and admitted by the judge.

In the absence of automatic disclosure, the availability of all relevant information is ensured through the mandatory submission of the administrative record (expediente administrativo), as detailed in 8.1 Disclosure/Discovery. This requirement is a procedural obligation of the Public Administration, whose failure to meet it allows the court to draw inferences regarding the truth of the claimant’s allegations.

Furthermore, the process is governed by the rules of the Code of Civil and Commercial Procedure, which grant the judge the authority to order “measures for better viewing” (medidas para mejor proveer). This allows the court to request additional documents, expert reports or clarifications from government bodies or third parties to ensure that the decision is based on a complete understanding of the facts. Consequently, while the parties bear the burden of offering evidence, the court maintains an active role in gathering all information necessary for a proper judicial review.

In Argentina, it is possible to produce live evidence through the testimony of witnesses and the explanation of experts before the judge. Witnesses provide their testimony orally, and parties have the right to cross-examine them (repreguntar) to test the veracity of their statements.

However, the prevailing principle in administrative litigation is that the majority of the evidence is handled in writing. This includes not only the documentary evidence and the administrative record but also the technical reports and, in most cases, the final legal arguments (alegatos). While recent procedural reforms have sought to increase oral proceedings to improve efficiency, the core of the judicial review remains centred on the written file and the evidence previously gathered during the administrative stage.

In the majority of cases, it is mandatory to exhaust all available administrative remedies (agotamiento de la vía administrativa) before initiating judicial proceedings. This requirement is a procedural prerequisite that the judge must verify ex officio at the start of the case. The exhaustion of the administrative route is typically achieved by filing the necessary hierarchical appeals against the final administrative act, ensuring that the Public Administration has had the opportunity to review its own decision before judicial intervention.

Unlike other legal fields in Argentina, pre-trial judicial mediation (mediación previa obligatoria) does not apply to administrative litigation.

Furthermore, once the judicial challenge has been filed, it is mandatory to notify the Office of the National Treasury Attorney (Procuración del Tesoro de la Nación), which serves as the head of the State’s legal corps. This notification is a formal requirement to properly commence the process when the National State or its entities are defendants. Failure to comply with these preliminary steps may result in the dismissal of the legal action for being premature or for failing to meet essential procedural requirements.

The exhaustion of the administrative route is a mandatory prerequisite for judicial review and follows specific paths, depending on the nature of the administration’s action.

• Administrative acts of particular scope (Actos de alcance particular): to challenge an administrative act directed at a specific individual or entity, the hierarchical appeal (recurso jerárquico) must be exhausted.
• Administrative acts of general scope (Actos de alcance general): to challenge regulations or acts of general scope, a specific remedy known as an indirect administrative challenge (reclamo administrativo impropio) is required.
• Administrative claims for performance: in cases involving petitions for the administration to give, do or refrain from doing something – where no formal administrative act has yet been issued – a prior administrative claim (reclamo administrativo previo) is mandatory.

The exhaustion of these channels is verified once the highest authority issues a final decision or through administrative silence. If the administration fails to rule within the legal timeframe after a mandatory appeal or claim has been filed, the claimant may consider the request tacitly denied (denegatoria tácita). This allows the claimant to proceed to judicial review, ensuring that the administration’s failure to act does not indefinitely block access to the courts. The judiciary has the duty to verify the proper exhaustion of these stages ex officio.

In Argentina, the time limit for filing a judicial challenge depends on whether the Public Administration has issued an express decision or has remained silent.

• Express rejection: in a hierarchical appeal, indirect administrative challenge or prior administrative claim, if the competent authority issues an express rejection, the claimant has a mandatory period of 180 business days (días hábiles judiciales) in which to initiate judicial proceedings. This period is calculated from the day following the notification of the rejection.
• Administrative silence: if the administration fails to rule within the legal timeframes, constituting administrative silence or tacit denial (denegatoria tácita), there is no expiration period within which to bring the challenge. The judicial action may be initiated at any time, as long as the silence persists.

Failure to file the challenge within the 180-day limit after an express notification results in the decision becoming “firm” (firme), which precludes any further judicial review.

When initiating a claim, the claimant is required to provide and offer all the evidence necessary to prove their petition. This requirement ensures that the court has a clear understanding of the factual basis of the dispute from the outset.

The claimant must fulfil the following evidentiary requirements.

• Documentary evidence: the claimant must attach all documents in their possession that support their claim. If they do not have certain documents, they must identify them and state where they can be found.
• Offer of proof: in the initial filing, the claimant must specifically offer all other types of evidence they intend to produce, such as witnesses, expert reports or requests for information from other entities.

Failure to offer evidence at the time of filing generally precludes the claimant from doing so later, except in exceptional cases involving newly discovered facts.

The legal arguments and the offer of evidence are strictly required at the initial stage of the proceedings, specifically during the filing of the complaint (demanda) and the subsequent response (contestación de demanda).

The procedural development follows these key principles.

• Joinder of issue (Traba de la litis): once the response to the complaint is filed, the “litis” is joined, and the scope of the trial is strictly limited to the facts and legal arguments presented in those initial pleadings.
• Offer of proof: parties must offer all their evidence (documentary, witnesses, experts, etc) at this very first stage.
• Judicial determination: after the issue is joined, the judge reviews the evidence offered by the parties and orders the production of only that which is considered pertinent and necessary for the resolution of the case.
• Limited scope: the court will only consider the issues raised in the initial filings, ensuring that the judicial review remains focused on the specific “case” or “controversy” as defined by the parties’ initial claims and defences.

Once a claim is issued, it must undergo a preliminary sifting process conducted by the judge ex officio to determine its admissibility before proceeding to the merits of the case. The court applies a rigorous test to ensure the claim meets the following mandatory prerequisites.

• Jurisdiction (Competencia): the judge must verify that the matter falls within the specialised jurisdiction of administrative law and that the court is competent to hear the case based on subject matter and territorial rules.
• Exhaustion of administrative remedies: the court confirms that the claimant has properly exhausted all mandatory administrative channels, ensuring the administration had a final opportunity to review its decision.
• Timeliness: the judge verifies that the judicial challenge was filed within the mandatory legal timeframes (eg, 180 business days for express rejections), to ensure the claim is not time-barred.
• Existence of a “case” or “controversy”: the judiciary must ensure there is a concrete, personal and certain grievance rather than a request for an abstract legal opinion or a check on mere legality.
• Standing: the court examines whether the claimant is a subject legally enabled to pursue the specific interest or right being invoked.

The case may be dismissed at this early stage if the claim fails to meet any of these threshold requirements – particularly if the judge lacks jurisdiction or the administrative route was not exhausted.

Argentine law provides specific legal instruments for cases requiring urgent judicial intervention. These mechanisms allow for an expedited process where the standard requirement of exhausting the administrative route may be waived to prevent irreparable harm.

The primary tools for expedited relief are as follows.

• Acción de amparo: this is an expedited and summary constitutional remedy directed against any act or omission by a public authority that, in a current or imminent manner, injures, restricts, alters or threatens constitutional rights with manifest arbitrariness or illegality. To succeed, the claimant must prove that the judicial protection is needed urgently and that there is no other more appropriate judicial route available.
• Injunctive relief (Medidas Cautelares): claimants may request preliminary injunctions against the State to suspend the effects of an administrative act or to compel an urgent action while the main litigation is pending. The test for granting an injunction requires the claimant to demonstrate:
1. Verosimilitud del Derecho (fumus boni iuris) – a strong appearance of a valid legal right or a high probability that the claim will succeed on the merits; or
2. Peligro en la Demora (periculum in mora) – the existence of an objective risk such that, if the relief is not granted immediately, the final judgment would be rendered ineffective or the claimant would suffer irreparable damage.

In the Argentine legal system, judicial review of administrative actions entails a comprehensive examination of the challenged decision to ensure its conformity with the legal order and constitutional principles. The court’s primary function is to resolve effective collisions of rights through the exercise of jurisdiction in a “case” or “controversy”, rather than performing a mere abstract check of legality.

The scope of this judicial scrutiny includes the following.

• Legality and arbitrariness: the judge verifies the legal and factual basis of the act, ensuring that the administration has not acted with manifest arbitrariness or in violation of the principle of reasonableness.
• Merits, opportunity and convenience: the court is empowered to analyse the reasons linked to the opportunity, merits or convenience (oportunidad, mérito o conveniencia) of the impugned act, as well as its impact on the public interest.
• Effective judicial protection: the review is guided by the principle of effective judicial tutelage (tutela judicial efectiva), which guarantees that the judiciary can provide a real remedy when a legally protected interest is at stake.

While the judiciary must respect the administration’s discretion, it is fully authorised to annul any decision that is found to be unreasonable, disproportionate or contrary to the public interest.

Argentina is governed by a written National Constitution, which functions as the supreme norm of the legal system, meaning that any act or decision issued by the Public Administration must comply with its principles. It is entirely possible to challenge a State act on the basis that it is inconsistent with the Constitution, either by invoking unconstitutionality as a fundamental ground for the nullity of the act within a proceeding or through a specific action for unconstitutionality.

For such a challenge to be admissible, the judiciary requires the existence of a concrete “case” or “controversy” where a specific injury to a right is demonstrated, as courts do not issue abstract legal opinions on the validity of norms. This system ensures that the judiciary maintains the ultimate authority to invalidate any administrative action that departs from the constitutional text – a power that is vested in any judge across all instances and jurisdictions, upholding the protection of fundamental guarantees.

In Argentina, compliance with the mandatory administrative procedure is considered an essential element for the validity and legality of any State action. Consequently, it is entirely possible to challenge a government decision on the basis that the decision-maker failed to follow the relevant procedural requirements. Under the Administrative Procedures Act, the failure to observe the established procedures – such as the right to be heard, the right to present evidence, or the requirement to obtain a reasoned legal opinion prior to the issuance of the act – renders the decision legally defective. Such procedural flaws constitute grounds for the act to be declared null by a court.

In the Argentine legal system, the legality of the “cause” (causa) is one of the essential requirements for the validity of an administrative act. The cause consists of the factual and legal precedents that serve as the foundation for the decision; therefore, the legality of the act depends on the truthfulness and accuracy of these elements. If a decision is based on an error of fact (either because the invoked facts do not exist or because they were falsely interpreted), the affected party is fully entitled to seek a judicial declaration of nullity. The judiciary has the authority to review whether the factual premises upon which the administration based its will are true and sufficient, ensuring that the exercise of public power is not arbitrary and does not rely on erroneous factual foundations.

In Argentina, it is possible to challenge an administrative action on the basis that the decision-maker improperly abdicated or fettered their discretion, as even discretionary powers are subject to the principles of reasonableness and non-arbitrariness. While the Public Administration enjoys a margin of discretion in certain matters, this power is never absolute and must always be exercised within the limits of the law and the public interest. The judiciary is empowered to evaluate the reasonableness of such discretionary decisions; if the court finds that the administration acted outside the bounds of rationality or proportionality, it can declare the act null to ensure that the exercise of power remains within legal and constitutional constraints.

In the Argentine legal system, the will of the administration is a fundamental requirement for the validity of any administrative act. For an act to be legitimate, the will of the decision-maker must be formed freely, without any defects such as error, fraud or coercion. If the administrative will is found to be impaired or nullified for any of these reasons, the resulting act is legally defective and can be challenged in court. The judiciary is empowered to examine the internal formation of the administration’s decision; if it determines that the will was not validly expressed or was distorted, it may declare the act null to ensure that State actions are the product of a lawful and reasoned process.

Under the Argentine legal system, a challenge based on unequal treatment is anchored in the constitutional principle of equality before the law. Any administrative act that creates arbitrary distinctions or fails to treat individuals in identical circumstances equally is considered unconstitutional. The affected party may seek a judicial declaration of nullity or unconstitutionality, as the judiciary must ensure that State actions are reasonable and not discriminatory. Consequently, unless the administration can provide an objective and proportional justification for the differential treatment, the act will be invalidated for violating constitutional mandates.

Argentina is a signatory to the American Convention on Human Rights (Pact of San José, Costa Rica) and has granted constitutional hierarchy to several international human rights treaties. Consequently, it is entirely possible to bring a claim on human rights grounds, as these international instruments are directly applicable and prevail over domestic laws. The judiciary is bound to perform a “conventionality control” (control de convencionalidad) to ensure that State actions and regulations are consistent with the standards established by the Inter-American Court of Human Rights. If a government decision violates a fundamental right protected by these treaties, the affected party can seek its annulment or the cessation of the violation through domestic courts.

In the Argentine legal system, a claim can be brought on proportionality grounds as it is a core component of the principle of reasonableness. Any administrative act or regulation must maintain a proportional relationship between the factual circumstances, the means chosen by the administration, and the legitimate public interest objective being pursued. If a government decision is deemed excessive or unnecessary, or lacks a rational connection to its stated purpose, it is considered arbitrary and unconstitutional. The judiciary is empowered to review the proportionality of State actions and may declare them null if they result in an unreasonable restriction of individual rights or exceed the bounds of administrative discretion.

Under the Argentine administrative legal framework, the validity of a government decision depends on the fulfilment of specific essential requirements, including:

• the competence of the issuing authority;
• a valid will free from error or coercion;
• a factual and legal basis (cause);
• a certain and legally possible object; and
• compliance with all mandatory procedures, including the right to be heard and to obtain prior legal counsel.

In addition, the act must be properly reasoned (motivation) and pursue a legitimate public purpose without hidden motives, ensuring all measures are reasonable and proportionate to that end. The failure to meet any of these essential elements renders the administrative act defective and subject to a judicial declaration of nullity.

In the Argentine legal system, certain government decisions known as “non-justiciable political acts” (cuestiones políticas no justiciables) are generally exempt from judicial review. These decisions typically involve matters of high-level State policy or constitutional functions specifically reserved for the executive or legislative branches, such as the declaration of a state of siege, the appointment of certain high-ranking officials, or the conduct of foreign relations.

However, the scope of this exemption has been progressively narrowed by the judiciary. Even in these cases, courts may still intervene if the decision violates fundamental constitutional guarantees or if the administration fails to follow the mandatory legal procedures for its issuance. Consequently, while the merits of a political decision may be shielded from review, its legality and conformity with constitutional rights remain subject to judicial scrutiny.

In Argentine administrative litigation, the defendant (typically the State) submits its grounds of defence when filing the formal answer to the complaint (contestación de demanda). This follows the service of notice of the lawsuit. Before addressing the merits, the State often raises preliminary objections, such as the failure to exhaust mandatory administrative remedies or the lack of standing.

Commonly, the administration relies on the defence of discretionary powers, arguing that the challenged decision falls within its technical or political prerogative. In such cases, the State asserts that the judiciary should not substitute the administration’s judgment with its own, provided the act is not manifestly arbitrary.

It is possible to apply for interim relief (medidas cautelares) to protect rights or ensure the effectiveness of a final judgment. Under the Interim Measures Against the State Act (Law 26.854), these measures are common to prevent the duration of the proceedings from causing irreparable harm to the claimant. The most frequently sought forms include:

• the suspension of the effects of the administrative act;
• the prohibition to innovate to maintain the status quo; and
• innovative measures or positive injunctions that require the administration to perform a specific action.

To obtain such relief, the claimant must demonstrate the likelihood of success on the merits (verosimilitud del derecho) or a danger in delay (peligro en la demora), and that the measure does not significantly prejudice the public interest.

Damages may be awarded through a judicial claim filed either alongside an action for nullity or as a separate proceeding. Under the State Liability Act, compensation for unlawful acts requires proving a specific injury, an irregular state action and a direct causal link.

In cases of lawful state acts, liability is more restrictive and requires demonstrating a “special sacrifice” – a disproportionate and individualised burden that exceeds common public charges. In these instances, compensation is limited to the actual loss (daño emergente) and specifically excludes lost profits.

Any judge can declare a law or regulation unconstitutional. In the Argentine “diffuse” system of judicial review, this power is not reserved for a specific constitutional court; rather, every judge has the duty to ensure that legislation aligns with the Constitution.

A declaration of unconstitutionality typically applies only to the specific case at hand (inter partes effects), meaning the law remains in force for the rest of the public but is not applied to the claimant. However, in certain collective actions or “class actions” (procesos colectivos), the Supreme Court has recognised that a ruling may have general effects (erga omnes) if it involves indivisible rights or affects a specific group uniformly.

Courts have the authority to order the government to carry out a specific course of action through both interim relief and final judgments. This is often achieved through positive injunctions (medidas cautelares innovativas), which require the public entity to perform a specific act to prevent irreparable harm during the proceedings. In a final ruling, the judiciary may also issue a mandatory injunction ordering the administration to act when it has unlawfully failed to fulfil a legal duty.

Despite this power, Argentine administrative courts generally maintain a degree of deference toward the Executive Branch. In matters involving administrative discretion, judges typically refrain from substituting the administration’s technical or political judgment with their own. Instead of dictating a specific outcome, the court will often annul the unlawful act and remand the case to the Executive, requiring a new decision that complies with the legal parameters set forth in the ruling.

Under Law 19.549, a declaration of absolute nullity renders the administrative act null with retroactive effect to the date it was issued. The primary objective is to restore the situation to its original state as if the unlawful act had never occurred.

Following such a ruling, the claimant is entitled to initiate an action against the State for compensatory damages resulting from the illegitimate act. While the court’s main role is to annul the illegal decision, the administration may be required to issue a new act that complies with the court’s legal findings or to perform the duty it had previously neglected.

The National Civil and Commercial Procedural Code allows claimants to request the benefit of litigating without costs (beneficio de litigar sin gastos) upon proving a lack of sufficient financial resources. This mechanism provides a total or partial exemption from court fees and legal expenses unless the claimant’s financial status improves.

If the claimant wins the lawsuit, their liability for legal costs is capped at one-third of the total amount awarded.

Under the general rule established in the National Civil and Commercial Procedural Code, the losing party is required to pay all legal costs, including the attorney fees of the successful party. However, judges have the discretion to depart from this “loser pays” principle if they find sufficient merit to do so, such as when the case involves a novel or complex legal issue or a matter of significant public interest.

In such instances, courts often declare that costs are to be borne “in the order caused” (costas por su orden), meaning each party pays its own expenses and half of the common court costs.

In exceptional cases, legal representatives may be held liable for costs resulting from their exclusive fault or negligence, provided this is specifically declared by the court. Under the procedural code, a representative is required to reimburse the client for costs judicially determined to have been caused by such conduct. Based on the circumstances, the judge may also establish joint and several liability (responsabilidad solidaria) between the representative and the sponsoring lawyer (letrado patrocinante), ensuring that the financial burden of professional errors falls on the individuals responsible.

In the federal jurisdiction, judgments issued in administrative challenges are appealable. Generally, the appeal must be filed within five days of the notification of the ruling. It is important to note that these specific timeframes and procedures apply to the federal courts; provincial jurisdictions operate under their own distinct procedural codes, which may establish different requirements.

Appeals against first-instance rulings are heard by the Federal Administrative Court of Appeals (Cámara de Apelaciones en lo Contencioso Administrativo Federal). A subsequent recourse to the National Supreme Court of Justice is available only if strict admissibility requirements are met (primarily through the Extraordinary Federal Appeal), such as the existence of a federal question or manifest arbitrariness. The Supreme Court is the final judicial authority and does not act as a standard third instance for reviewing facts or evidence.

While formal “permission” is not required, appeals in the federal jurisdiction are subject to specific admissibility requirements. The lower court’s role is limited to verifying that the appeal was filed within the statutory period and that the decision is legally appealable, which generally includes final judgments, interlocutory rulings and orders causing irreparable harm.

Crucially, an appeal is only admissible if the amount in controversy exceeds a minimum jurisdictional threshold set annually by the Supreme Court. If the claim’s value falls below this limit, the decision is deemed unappealable by reason of the amount. Should the lower court deny the appeal on formal or monetary grounds, the appellant may seek direct review from the higher court through a motion for direct review (recurso de queja). In such cases, the Court of Appeals determines whether the appeal was correctly denied and, if not, grants it for consideration.

An appeal is not a new trial. Instead, it is a review of the lower court’s decision based strictly on the facts and evidence already presented during the initial proceedings.

The appellate court’s scope is limited to the specific points of the judgment that the appellant challenges through their written grievances. Consequently, the court cannot rule on issues that were not raised before the first-instance judge, nor can it reconsider the entire case as if it were starting over. The production of new evidence at the appellate level is generally prohibited and is only permitted in highly exceptional circumstances provided by law.