What Is Private Prosecution (Acusación Particular) & How Is It Exercised?

What is private prosecution (acusación particular) and how is it exercised?

When someone suffers a crime, their first concern is usually that the person responsible is investigated, tried, and convicted. For this purpose, there is the public prosecutor’s office, which acts on behalf of the State and has the obligation to prosecute public offenses. But the Spanish criminal system offers the victim something more than blind trust in the prosecution: it gives them the possibility of taking control of their own case and actively participating in the proceedings as a prosecuting party. This mechanism is called acusación particular (private prosecution).

Private prosecution is one of the most characteristic and most valuable institutions of the Spanish criminal process. Unlike other European legal systems where the victim has a passive and subordinate role, in Spain the victim can exercise criminal action with full autonomy, propose evidence, appeal unfavorable decisions, and sustain the prosecution even when the public prosecutor decides not to do so. This possibility makes a huge difference in practice: a process in which the victim exercises private prosecution is a more controlled, more active process with greater guarantees that the case will reach trial.

In this article we explain exactly what private prosecution is, who can exercise it, how it is constituted, what rights and obligations it entails, how it differs from popular prosecution, and when it is advisable to exercise it. A clear understanding of this legal figure can be decisive for someone who has suffered a crime and wants justice to be done.

What is private prosecution (acusación particular)?

Private prosecution is the procedural figure by which the direct victim of a crime —or their relatives in the most serious offenses— becomes a prosecuting party in the criminal proceedings, exercising criminal action alongside the public prosecutor or, in certain cases, independently from it. It is an institution exclusive to Spanish procedural law that has no exact equivalent in most European legal systems.

From a legal standpoint, private prosecution turns the victim into an active party in the criminal proceedings, with the same procedural rights as the public prosecutor with regard to the accusation: they can propose investigative measures, submit written pleadings, propose evidence for trial, question witnesses and experts, present their own oral arguments during the trial, and appeal all decisions that are unfavorable to them, including a possible acquittal.

Private prosecution does not replace the public prosecutor: both accusations act in parallel, although their objectives may not be exactly identical. The prosecutor represents the public interest in prosecuting crime, while the private prosecution represents the specific interests of the victim, which include both the conviction of the offender and obtaining appropriate compensation for the harm suffered. In practice, having private prosecution significantly strengthens the prosecuting position in the proceedings.

Who can exercise private prosecution?

Standing to exercise private prosecution corresponds, first of all, to the direct victim of the crime, that is, the natural or legal person who has directly suffered the harm resulting from the criminal conduct. In crimes where the victim has died as a result of the offense —homicide, murder, negligent homicide— their heirs and close relatives may exercise private prosecution: the spouse or partner, children, parents, and, in certain circumstances, other relatives who can prove their status as injured parties.

Legal persons —companies, associations, foundations— may also exercise private prosecution when they have been victims of a crime: fraud, misappropriation, intellectual or industrial property offenses, or any other unlawful act that has caused direct harm to the entity. In these cases, the legal person acts through its legal representative or a duly authorized person.

There is also the possibility that several victims of the same crime join together to exercise private prosecution jointly, which is especially common in cases of mass fraud, consumer offenses, or scams affecting a large number of people. In these cases, coordinated action by multiple private prosecutors adds additional strength to the proceedings and allows costs to be shared.

How is private prosecution constituted?

To exercise private prosecution, it is not enough to have filed a complaint. It is necessary to formally appear in the criminal proceedings by means of a written submission addressed to the competent investigating court, in which the intention to exercise criminal action as a private prosecutor is declared. This document must be signed by a lawyer and a procurator, whose intervention is mandatory from the moment the victim decides to appear as a party.

The moment to appear as a private prosecutor may vary: it can be done from the outset of the proceedings —by directly filing a querella— or at a later stage, once the court has opened the investigation. The law establishes a maximum time limit to appear, which in abbreviated proceedings is before the investigation phase concludes. If this deadline is missed, the possibility of exercising private prosecution may be closed.

Once they have appeared, the private prosecutor must actively participate in the proceedings: receive notifications from the court, submit the appropriate written pleadings at each stage, propose the investigative actions deemed necessary, and, when the time comes, submit the indictment in which they formally set out the charges, legally classify the facts, and request the penalty and compensation they consider appropriate.

Rights of private prosecution

Once formally constituted as a party, the private prosecution has a set of procedural rights that allow active participation in all phases of the proceedings:

• The right to be notified of all decisions issued by the court during the investigation and subsequent phases.
• The right to access the case file and obtain copies of the proceedings, except during periods of secrecy of the investigation.
• The right to propose investigative measures during the investigation: witness statements, expert reports, searches, interceptions, or any other action that may help clarify the facts.
• The right to appeal unfavorable decisions, including orders of dismissal or closure of the investigation before trial.
• The right to file an indictment in the intermediate phase, establishing the facts, legal classification, and requested penalty and compensation.
• The right to propose evidence for trial and actively participate during the hearing: question the accused, examine witnesses and experts, and cross-examine those of the defense.
• The right to present oral arguments at the end of the trial, setting out final conclusions.
• The right to appeal the judgment if the outcome is considered unjust: whether due to insufficient penalty, acquittal when conviction was appropriate, or inadequate compensation.

Obligations of private prosecution

Exercising private prosecution entails not only rights but also a series of procedural obligations that must be fulfilled to maintain party status and avoid negative consequences:

The most important is to act in good procedural faith and not maintain accusations known to be unfounded. A private prosecution that persists in unsupported charges may be ordered to pay the costs of the proceedings if the judgment is acquittal, which can represent a significant financial burden.

In addition, the private prosecution must appear at procedural acts when summoned, submit pleadings within established deadlines, and maintain a loyal and transparent attitude in exercising procedural rights. Repeated failure to comply may lead the court to limit their intervention or, in extreme cases, consider that they have withdrawn from the prosecution.

Difference between private prosecution and popular prosecution

A distinction that often causes confusion is that between private prosecution and popular prosecution. Although both are ways of exercising criminal action outside the public prosecutor, their basis, requirements, and conditions differ.

Private prosecution is reserved for the direct victim of the crime or their relatives when the victim has died. It is based on the right of the injured party to actively participate in the process seeking to repair the harm and punish the offender. It does not require posting a bond.

Popular prosecution, on the other hand, may be exercised by any Spanish citizen —or legally constituted association— even if they are not a victim and have suffered no direct harm. It reflects society’s interest in prosecuting certain crimes of particular public relevance, such as corruption offenses, crimes committed by public officials, or those affecting collective legal interests. Popular prosecution generally requires posting a financial bond set by the court.

In terms of procedural strength, private prosecution tends to have a stronger position in practice, as courts usually grant it greater legitimacy due to its direct connection with the victim.

When is it advisable to exercise private prosecution?

The decision to exercise private prosecution is not always obvious or automatic. It involves financial costs —lawyer and procurator fees— and an active commitment to a process that may last years. Therefore, it is advisable to assess with professional guidance whether it is the most appropriate option in each case.

Private prosecution is especially recommended when the victim has specific interests to protect beyond the mere conviction of the offender, such as significant financial compensation, recovery of assets, or specific reparation. It is also advisable when there is a risk that the public prosecutor may not act diligently or when the victim wants to ensure the possibility of appealing the case if the prosecution does not.

In serious crimes —sexual assaults, homicides, major economic crimes— exercising private prosecution is practically essential to ensure that the victim’s interests are properly represented throughout the process, from investigation to enforcement of the judgment.

In less serious offenses, or when the victim has no significant financial claims, it may be sufficient to file a complaint and rely on the public prosecutor, reserving the option to appear later if the process does not progress as expected.

The role of the lawyer in private prosecution

Exercising private prosecution without a specialized criminal lawyer is practically impossible, not only because the law requires it, but because the technical complexity of criminal proceedings demands deep legal knowledge and solid practical experience.

The lawyer for the private prosecution must thoroughly understand the case from the outset, propose the most effective investigative measures, draft the indictment with technical precision, prepare the trial strategy, and handle appeals throughout the process. They must also advise the client on whether to maintain the accusation or reach an agreement with the accused that includes satisfactory compensation in exchange for withdrawing the private prosecution.

At our firm, we have lawyers specialized in representing victims throughout the criminal process. If you have suffered a crime and want to know whether it is advisable to exercise private prosecution in your case, consult us with no obligation.

Frequently asked questions

Can I exercise private prosecution if I have already filed a complaint without a lawyer?
Yes. Having previously filed a complaint without legal assistance does not prevent you from later appearing as a private prosecutor in the proceedings. You must hire a lawyer and procurator and file a formal appearance within the legal deadline. However, you cannot wait indefinitely: if the deadline expires, the possibility may be permanently lost.

Can private prosecution maintain the accusation if the prosecutor requests acquittal?
Yes, and this is one of its main advantages. If the prosecutor changes their position after trial and requests acquittal, the private prosecution may independently maintain the request for conviction. The court must rule on both positions and may convict even if the prosecutor requested acquittal.

What happens if the accused and the victim reach an out-of-court settlement?
If they reach an agreement —for example, compensation in exchange for withdrawal— the victim may withdraw the private prosecution. However, in public offenses this does not automatically end the proceedings: the prosecutor may continue. The agreement may mitigate the penalty but does not extinguish the case except in private or semi-public offenses.

Can private prosecution claim higher compensation than the prosecutor?
Yes. Private prosecution may request different —usually higher— compensation than the prosecutor, including all specific damages: moral harm, lost profits, expenses, labor damage, and any other provable loss.

Can private prosecution be exercised if the crime occurred a long time ago?
It depends on whether the offense has prescribed and whether proceedings are still open or can be reopened. If the crime is time-barred, no criminal process can proceed. If not, and the case was closed, it may be reopened with new evidence. In any case, acting promptly is essential, as limitation periods vary depending on the seriousness of the offense.