How Long Can a Police Detention Last in Spain?

How long can a police detention last in Spain?

When someone is detained — whether oneself or a family member — one of the first questions that arises is always the same: how long can they keep me here? The answer is not arbitrary nor does it depend on the will of the officers: it is strictly regulated by the Spanish Constitution and by the Criminal Procedure Act, which establish maximum time limits that the police are obliged to respect under penalty of incurring illegal detention.

The duration of police detention is one of the fundamental guarantees of the rule of law. Its precise regulation has a clear objective: to prevent deprivation of liberty from lasting longer than strictly necessary for the investigation and to ensure that, if the situation must continue, it is a judge — and not the police — who decides and controls it. Police detention cannot be indefinite nor can it become a tool of pressure.

In this article we explain how long police detention can legally last in Spain, when those time limits can be extended, what happens when they expire, and what legal mechanisms exist to challenge a detention that is prolonged unlawfully. A precise understanding of these time limits is essential for someone who is detained or for someone who has a family member in that situation.

The general time limit: the constitutional 72 hours

Article 17.2 of the Spanish Constitution clearly establishes that preventive detention may not last longer than the time strictly necessary to carry out investigations aimed at clarifying the facts and that, in any case, within a maximum period of seventy-two hours the detainee must be released or placed at the disposal of the judicial authority.

This 72-hour period — three calendar days, not working days — is the basic constitutional limit that governs the vast majority of police detentions in Spain. It means that, at most, once 72 hours have passed since the moment of detention, the police must do one of two things: either release the detainee — with or without charges — or bring them before the duty judge so that the judge can decide on their situation.

The calculation of the time limit begins at the exact moment of detention, not from when the detainee arrives at the police station nor from when questioning begins. If the detention takes place at three in the morning on a Saturday, the 72 hours are counted from that precise moment, regardless of whether it is a weekend or a public holiday. The calendar does not interrupt or suspend the time limit.

During those 72 hours, the police may carry out all investigative actions they consider necessary: take a statement from the detainee — with the corresponding legal guarantees —, carry out identifications, collect biological samples when authorized, conduct line-ups, and any other action aimed at clarifying the facts. But once the time limit has expired, any further detention is illegal and gives rise to criminal liability for the officers who prolong it.

When can detention be extended beyond 72 hours?

The general 72-hour limit has a single exception expressly provided for in the Constitution: offenses related to armed groups or terrorist organizations. In these exceptional cases, Organic Law 4/1988 allows the detention period to be extended beyond 72 hours, but always under strict judicial control.

In such cases, the police may request from the competent judge — the National Court in most terrorism cases — an extension of detention of up to an additional 48 hours, raising the maximum total period to five days. This extension is not automatic: it requires a reasoned judicial decision that assesses whether the conditions justifying it are present and whether it is necessary for the proper course of the investigation.

Outside the scope of terrorism, there is no legally possible extension of police detention. Any police custody exceeding 72 hours without prior judicial authorization in cases unrelated to terrorism constitutes illegal detention, regardless of the seriousness of the investigated offense or the reasons the police may allege to justify it.

Detention must last “the time strictly necessary”

The Constitution not only sets a maximum limit of 72 hours: it also imposes a principle of necessity and proportionality that requires detention to last only the time strictly necessary to achieve its purposes. This means that if the police complete their investigations earlier — because the detainee is identified, because the doubts that motivated the detention are resolved, or because it is determined that there is no basis to continue — they must release the detainee immediately, without waiting for the maximum period to expire.

This principle has an important practical consequence: the detainee does not have to wait the full 72 hours if it is determined earlier that there are no sufficient grounds to continue the detention. If the lawyer considers that the necessary investigations have been completed and that there is no basis to maintain detention, they may request the immediate release of the client, and the police must assess whether that request is justified.

However, in practice, the police usually use the full time limit when they consider that the investigation requires it, and detainees are rarely released before the available time is exhausted, especially in more serious cases. The lawyer’s oversight is essential to ensure that the time limit is not used abusively or as pressure to force the detainee to make a statement.

What happens at the end of the time limit: release or being brought before a judge

When the detention period expires — whether the ordinary 72 hours or the 120 hours in terrorism cases with extension — the police have two options, and only two:

Release

If the police conclude that there are not sufficient indications to continue the criminal process, or if they consider that the detainee can be released without risk of flight or destruction of evidence, they must release them immediately. This release may occur with or without charges: if complaints have been formalized or indications have been gathered during detention, the process may continue even if the detainee is released, and they may later be summoned to testify as a suspect.

Release at the end of detention does not mean the case is closed or that the police have stopped investigating. It simply means that, for the moment, there is not enough basis to maintain deprivation of liberty. The process may continue, and the released detainee may receive a summons from the court in the following days or weeks to appear as a suspect.

Being brought before a judge

If the police consider that there are sufficient indications of criminal responsibility and that it is necessary for a judge to assess the detainee’s situation, they bring them before the duty investigating court. At this point, a new phase begins that is no longer under police control but under judicial authority.

Before the duty judge, the detainee — assisted by their lawyer — appears in what is known as a pre-trial detention hearing, in which the judge hears the version of the police and the prosecutor regarding the need to maintain deprivation of liberty, also hears the arguments of the defense lawyer, and decides whether to order provisional release, pre-trial detention, or some intermediate precautionary measure.

Pre-trial detention: when the judge prolongs deprivation of liberty

Pre-trial detention is the measure by which the judge, once the detainee has been placed at their disposal, decides to maintain deprivation of liberty during the course of the proceedings. It is no longer police detention: it is a judicial precautionary measure with its own time limits, requirements, and guarantees.

For the judge to order pre-trial detention, several requirements must be met: the existence of reasonable indications of criminality, the presence of one of the material grounds provided by law — risk of flight, risk of reoffending, risk of destruction of evidence, or danger to the victim — and the proportionality of the measure in relation to the seriousness of the offense investigated.

The maximum time limits for pre-trial detention are significantly longer than those for police detention and vary depending on the seriousness of the offense: as a general rule, pre-trial detention may not exceed one year, extendable up to two years when the possible sentence does not exceed three years, and may extend up to two years, extendable up to four, in more serious offenses. These time limits represent the absolute maximum, and the judge must periodically review whether the measure remains justified.

Detention under incommunicado regime

In certain exceptional cases, a judge may order that detention be carried out under incommunicado conditions, temporarily limiting the detainee’s right to communicate with the outside world. This measure, mainly reserved for terrorism offenses, large-scale drug trafficking, and other particularly serious crimes, aims to prevent the detainee’s communication with the outside from frustrating the investigation or endangering others.

Incommunicado detention cannot be ordered by the police: it requires a reasoned judicial decision and has a maximum duration. During incommunicado detention, the detainee retains the right to legal assistance, although in this case the lawyer will be court-appointed and cannot be chosen by the detainee or their family. The detainee also cannot communicate privately with that lawyer: communication with the lawyer takes place in the presence of officers.

Incommunicado detention is an extremely restrictive measure that the European Court of Human Rights has examined on numerous occasions, establishing that it can only be maintained when there is objective and sufficient justification and that it must be subject to rigorous judicial control. Its improper or excessive use can be challenged before national courts and before the Strasbourg Court.

Habeas corpus: the safeguard against illegal detention

Habeas corpus is the constitutional mechanism specifically designed to protect individuals against unlawful detention. Regulated by Organic Law 6/1984, it allows the detainee themselves, their lawyer, or any person on their behalf to request that a judge examine the legality of the detention and order immediate release if it is unlawful.

Habeas corpus is an extremely urgent procedure: the judge must decide within hours of receiving the request. It is not necessary to wait for an investigation to begin or for any additional time to pass. If the judge finds that the detention is illegal — because time limits have been exceeded, because legal requirements are not met, or because fundamental rights of the detainee are being violated — they order immediate and unconditional release.

The grounds that may justify requesting habeas corpus are the following:

• The detention has been carried out without legal requirements — without a flagrant offense, without sufficient indications, or without identification as an authority officer—.
• The detainee’s whereabouts are unknown to their relatives and the detention has not been communicated.
• The maximum legal time limits have been exceeded without release or being brought before a judge.
• The detainee is being subjected to unlawful detention conditions, such as ill-treatment, deprivation of sleep, or lack of medical care.
• Fundamental rights of the detainee are being violated during deprivation of liberty.

Liability for exceeding detention time limits

Exceeding the maximum detention time limits is not a minor irregularity: it constitutes the offense of illegal detention as defined in the Criminal Code, which may give rise to criminal liability for the officers and superiors who ordered or allowed the unlawful extension of detention. In addition, it generates State liability toward the affected person, who may claim compensation for damages suffered.

In practice, cases of police detention exceeding legal time limits without judicial authorization are relatively rare, because officers are aware of the consequences of such irregularity. However, situations do occur in which the calculation of the time limit begins incorrectly or in which certain actions — such as transfers between police stations or waiting periods for investigative procedures— are carried out in a way that consumes time without the detainee or their lawyer being aware of it.

For this reason, it is essential that the lawyer verifies from the outset the exact moment of detention and precisely monitors the time limit, alerting the police and the court if the limit is approaching without the detainee having been brought before a judge.

Frequently asked questions

Is the 72-hour period counted in calendar hours or working days?
The 72-hour period is counted in calendar hours, that is, continuously and uninterruptedly from the exact moment of detention. It is not interrupted by weekends, public holidays, or nighttime hours. If the detention takes place on Friday at 20:00, the time limit expires on Monday at 20:00, regardless of the weekend. The time always runs without pauses. This is precisely one of the reasons why the lawyer must know and control the exact time of detention from the outset.

Can the police arrest me again for the same facts after releasing me?
Yes, although with important limitations. Once a person has been released at the end of detention, they may be arrested again for the same facts if new evidence appears or if the investigation reveals circumstances that were not previously available. However, if they have already been brought before a judge and the judge has ordered provisional release, a new police arrest for the same facts would require new circumstances justifying a review of that judicial decision. Under no circumstances can the police ignore a judge’s decision to release a person and arrest them again without new grounds.

What happens if I am arrested on a Friday afternoon and no duty judge is immediately available?
Duty courts operate 24 hours a day, 365 days a year, precisely to guarantee judicial control of detentions at any time. The lack of immediate availability of a judge does not justify exceeding the maximum detention time limit: if it is necessary to bring the detainee before a judge and the time limit is about to expire, the police must act immediately, even at night or on weekends. Judicial duty exists precisely for these cases. If the detainee is not brought before a judge within the time limit, that delay constitutes illegal detention.

How long can someone remain in pre-trial detention after being arrested?
Pre-trial detention, which begins when the judge orders it after the detainee has been brought before them, has its own time limits distinct from police detention. As a general rule, pre-trial detention may not exceed one year in offenses punishable by up to three years’ imprisonment, extendable up to two years in justified cases. For more serious offenses, it may reach two years, extendable up to four. In exceptionally complex cases, longer periods may apply. These limits represent absolute maximums: pre-trial detention must cease as soon as the conditions that justified it no longer exist, even if the maximum has not been reached.

Do I have the right to know exactly when my detention began?
Yes. The police are obliged to record in the report the exact time of detention and to communicate it to the detainee and their lawyer. This information is of enormous practical importance for controlling the maximum time limit. If the detainee or their lawyer believe that the time recorded in the report does not correspond to the actual moment of deprivation of liberty — for example, if the detainee was informally transferred before arriving at the police station— they may challenge that information before the judge and request that the time calculation be adjusted to the real moment when effective detention began, regardless of when the formal documents were signed.