Preventive detention in Belgium means that a person can be held in custody even before they’ve been convicted of a crime, right after the police make an arrest. If you find yourself caught up in criminal proceedings, it’s important to understand how pre-trial detention works in Belgium. Familiarizing yourself with important terms—like the arrest warrant (mandat d’arrêt), the regular judicial reviews of detention, and the rights of those detained (like access to a lawyer, being informed, and the possibility of bail)—can really impact how preventive detention is enforced.
This article aims to break down pre-trial detention, its limitations, and the rights of individuals who are detained. If you’re facing pre-trial detention, we’re here to guide and support you every step of the way.
What is preventive detention in Belgium?
Preventive detention in Belgium is a special measure that allows authorities to hold a suspect before they’ve been convicted. The goal is to prevent the suspect from fleeing, tampering with evidence, pressuring victims or witnesses, or committing further crimes. This measure can only be used when three specific conditions are met. First, there must be serious indications of guilt; the investigating judge needs to find enough evidence linking the suspect to the case at hand. Second, the detention must be necessary for public safety or the investigation itself, as pre-trial detention is seen as a last resort (other options, like conditional release, should be considered first).
Lastly, the detention must be backed by an arrest warrant (mandat d’arrêt). The investigating judge is required to provide a detailed explanation of why preventive detention is necessary. It’s important that preventive detention is justified, proportionate, and regularly reviewed by a judge to ensure it doesn’t extend longer than absolutely necessary.
Under what conditions can someone be detained in Belgium?
It is possible to detain someone in Belgium only under certain conditions, and even then it must always be kept within strict time limits. Generally speaking, a person cannot be detained for longer than twenty-four hours, without the intervention of an investigating judge.
From the moment of detention, whether by police or at the request of the public prosecutor, a 24-hour time-limit kicks in. Within that time limit, the detained individual must either be released, or brought before the investigating judge, who will decide whether to issue an arrest warrant. Moreover, immediately after the detention, a record must be created, “setting out the time and circumstances of the detention, the decision and actions ordered by the procureur du Roi, the manner of communication, and the time at which the concerned party was informed of the decision on detention.”
Article 12 of the Belgian Constitution states that no one may be deprived of their liberty for more than twenty-four hours after their arrest without the intervention of a judge. However, this period may be extended for an additional maximum of 24 hours, but only in exceptional circumstances and only if a prior, duly reasoned extension order has been issued and notified by the investigating judge.
Arrest in flagrante delicto
When a person is caught in the act of committing an offence, or immediately afterwards, the police may arrest them on the spot. This is known as arrest in flagrante delicto and is expressly permitted by law.
Arrest without flagrante delicto
If the person is not caught in the act, the police may only proceed with an arrest on the order of the public prosecutor (procureur du Roi). The prosecutor may request that the suspect be brought before the investigating judge for questioning. This power is explicitly provided for in the law governing preventive detention.
💡 In Belgium, no one can remain detained for more than 24 hours without seeing a judge
Investigating judge and the decision on preventive detention
If the examining magistrate considers that there are serious indications of guilt and that provisional detention is strictly necessary, they may order the detention of the accused and issue a detention warrant (mandat d’arrêt).
Before issuing this detention warrant, the examining magistrate must interrogate the accused about the facts alleged. In the context of this interrogation, the accused has the right to be assisted by a lawyer in that interrogation, and that right is one of the fundamental guarantees of defence. The detention warrant remains valid even where the legal obligation to hold a hearing does not occur, as a result of a force majeure circumstance. The detention warrant which authorises pre-trial detention is valid for five days from the moment it is notified.
Within a maximum of five days following the issuance of the arrest warrant, the accused must appear before the Council Chamber, assisted by their lawyer. The Council Chamber will assess both the legality of the arrest warrant and the necessity of maintaining preventive detention. This measure is subject to judicial review every three months. In addition, the detainee may submit a request for release once a month. The Council Chamber may decide to lift the arrest warrant and order the release of the accused, or it may decide to maintain preventive detention.
Judicial orders relating to preventive detention in Belgium
An investigating judge must intervene in order for any person to be deprived of liberty for a period longer than the first 24 hours. Below are the explanations of the different judicial orders under the Law of 20 July 1990 on preventive detention.
Order to appear (mandat d’amener)
This is the order by which the investigating judge instructs the police to bring the suspect before him to be interrogated. The law provides that the judge can make this request whenever the judge considers it necessary for the investigation. The person under investigation may be accompanied by a lawyer when interrogated.
Arrest warrant (mandat d’arrêt)
This is the decision by which an investigating judge authorises preventive detention. The arrest warrant can only be granted when the law has proven serious indications of guilt and when, “in the interest of public safety”, it is “absolutely necessary to deprive this person of his liberty”. The arrest warrant must provide written justification regarding the necessity of the detention and, at least inform the arrested of their rights, namely, the right to defence. With this warrant, the initiated 24-hour detention period, is now considered preventive detention, and is also subject to periodic reviews by the judiciary.
Why is this important? Without this document signed by a judge, lawful preventive detention does not exist. In Belgium, no one can be placed in pre-trial detention without a written, reasoned order issued by the investigating judge.
How long can preventive detention last in Belgium?
Preventive detention in Belgium isn’t something that can just go on forever. Its length is determined by three main stages:
Maximum duration of 5 Days
After the Arrest Warrant Once the interrogation is done and the investigating judge issues a mandat d’arrêt (arrest warrant), the law says this warrant is only valid for a maximum of five days. During this initial phase, the individual transitions from being held at the police station to being placed in pre-trial detention in a prison.
Mandatory monthly review by the Judge (council chamber)
Before those five days are up, the case has to be presented to the Council Chamber (Chambre du Conseil / Raadkamer). This judicial body must decide whether to keep the preventive detention in place or to release the individual (with or without conditions). If the detention continues, the judge is required to review it every month. The Council Chamber looks at factors like serious indications of guilt, the risk of flight, the potential for evidence to be destroyed, and public safety concerns. If any of these conditions change, the judge must order a release.
Possibility of a public hearing after 6 or 12 months
If the detention is extended, the detainee has the right to request a public hearing. According to the law, this can happen after 6 months for less serious offenses, or after 1 year for more serious crimes. This hearing gives the detained individual a chance to publicly argue why they think their continued detention isn’t warranted anymore.
Rights of detainees in preventive detention in Belgium
Deprivation of liberty is an exceptional measure, which is why there is a legal framework to guarantee the right to defence. Knowing one’s rights will make it easier to prevent abuses.
Right to know the reasons for the accompaniment
This means that from the moment a person is arrested, they have the right to know the reason for the deprivation of liberty and what the charges will be. The investigating judge is required to formulate the reasons for the arrest in a written document, it should contain what the alleged facts are, on what legal basis the arrest is carried out, and it must also state the grounds to justify the detention following the arrest (a risk of flight, destruction of evidence, renewal of offence, etc…).
Right to legal assistance
According to Belgian law, any detained person is entitled to consult with a lawyer from the very first hours of the deprivation of liberty and during the judicial interrogation. The detainee can communicate with a lawyer, can be assisted by a lawyer during the hearing before the investigating judge, and can also obtain a copy of the decision or judgment by which the detention is ordered.
Right to judicial review
Preventive detention cannot automatically be prolonged. Every 30 days, the Council Chamber (Chambre du Conseil / Raadkamer) reviews whether continued detention remains necessary. During these reviews, the detainee may request release or propose alternative measures (conditional release or bail). The monthly review acts as a safeguard against arbitrary detention.
Right to appeal judicial decisions
The detainee may appeal the decision of the Council Chamber before the Indictment Chamber of the Court of Appeal. If they believe that the law or a procedural principle has been violated, they may file an appeal in cassation before the Court of Cassation, which serves as the ultimate guardian of legality. For more information on expunging criminal records in Belgium, visit our specific article.
Right to request conditional release or release on bail
The law allows detention to be replaced by less restrictive measures, such as conditional release (for example, establishing a fixed residence, undergoing treatment, or avoiding contact with victims), or release on bail (cautionnement), which requires the deposit of a sum of money guaranteeing the accused’s appearance.
Temporary release and alternatives to preventive detention in Belgium
The most frequently sought alternative is a temporary release. The examining magistrate may order the release of the accused person with one or more obligatory conditions set. These conditions will be based upon the very facts that have led to consider a more serious measure of preventive detention. Article 35§3 states that the conditions must correspond to the case at hand and pursue objectives as set out in the law, such as ensuring appearance, preventing destruction of evidence, preventing the accused from committing a further offense and preventing the accused from contacting without due consideration other persons involved in the matter. Here are some of the most common measures of conditions or obligations:
- The requirement to abide at a fixed residence or required to live at a specific location.
- The prohibiting of communication with victims, witnesses or co-accused.
- The requirement to undergo or participate in medical, psychological or detoxification treatment, as defined.
- The prohibiting of travel beyond a defined area.
- The requirement to report or check in with local police or judicial officials.
The examining magistrate may be allowed to impose other requirements or modify the terms of the imposed obligations during the course of the investigation.
Release on bail (cautionnement)
Another alternative is release on bail. The judge may require full and prior payment of a bail amount (cautionnement), which they determine. The money is deposited with the Caisse des dépôts et consignations. Once the bail is paid and the receipt is presented, the Public Prosecutor orders the release. The bail is reimbursed once the accused fulfils all procedural obligations and appears before the court for the trial. If the accused fails to appear without legitimate reason, the bail is forfeited to the State.
Lifting of the arrest warrant
In addition to the alternatives above, the law provides that the arrest warrant may be lifted. The investigating judge has the authority to annul the warrant, which results in the immediate release of the detainee, provided that the circumstances of the case allow it. The judge issues a reasoned decision lifting the warrant, and the decision is immediately notified to the Public Prosecutor. This decision cannot be appealed, which speeds up the process.
Practical advice and successful case outcomes
If you find yourself in pre-trial detention in Belgium, it is essential to stay calm, immediately request the assistance of a lawyer specialised in Belgian criminal law, and avoid making any statements without legal guidance, as anything you say may directly influence the investigating judge’s decision regarding the arrest warrant.
Certain elements can be decisive in obtaining release under conditions, release on bail, or even the lifting of the arrest warrant. Remember that pre-trial detention must always remain exceptional, duly justified, and reviewed monthly by the Council Chamber, which is why an effective defence from the very first hours can significantly increase your chances of regaining your freedom while the criminal proceedings move forward.
Case 1: Revocation of an arrest warrant due to absence of flight risk
A citizen was arrested in Brussels for an alleged cybercrime. The Public Prosecutor requested an arrest warrant (mandat d’arrêt) claiming a risk of flight because the suspect did not hold Belgian nationality. After analysing the reasoning behind the warrant, the legal team demonstrated that M.R. had a permanent employment contract, a stable residence and a child enrolled in school in Belgium. At the first review before the Council Chamber, the defence successfully showed that the prosecutor’s arguments were insufficient.
Case 2: Granting of release on bail in an economic fraud case
In another case, L.S., an executive under investigation for fraud, was placed in pre-trial detention due to a perceived risk of evidence tampering. We proposed a substantial bail combined with a prohibition on contacting other suspects and a weekly reporting obligation to the police. The investigating judge accepted the arrangement, considering it sufficient to safeguard the integrity of the investigation.
Experience shows that cases involving pre-trial detention in Belgium can be resolved favourably when action is taken promptly, the grounds for the arrest warrant are examined in depth, and solid, realistic and legally compliant alternatives are presented.
Detained in Belgium? Act fast
If you have been detained in Belgium — or a family member is in this situation — it is crucial to act quickly. Preventive detention in Belgium is governed by strict deadlines, and every step can directly influence the investigating judge’s decision regarding your release.
The first priority is to request assistance from a lawyer. Do not make any statements without legal advice, do not sign documents you do not understand, and inform the authorities of any urgent needs, especially those affecting your health or well-being.
It may also be helpful, through your lawyer, to provide information about your personal situation (stable employment, fixed residence, family responsibilities) or any element that demonstrates strong ties to the community. These details can support a request for conditional release or release on bail.
Contact us at info@arthurmarin.com or +32 465 345 345 to receive urgent and personalised legal assistance if you are facing preventive detention in Belgium.
💡 The sooner you obtain professional legal advice, the greater your chances of regaining your freedom.
Frequently asked questions about preventive detention in Belgium (FAQ)
What is preventive detention in Belgium?
Preventive detention is a special legal measure that allows authorities to hold a suspect in custody before their trial. This can happen if there are strong signs of guilt and concerns like the possibility of fleeing, committing more crimes, or tampering with evidence.
How long can someone be held in preventive detention in Belgium?
Initially, preventive detention can last up to 5 days after an arrest warrant is issued. After that, the Council Chamber needs to review the case every 30 days. There’s no set maximum time limit, but the judge has to explain why continued detention is necessary at each monthly check-in.
How many hours can someone be held before seeing a judge?
Under Belgian law, the maximum time someone can be detained without seeing a judge is 24 hours. During this time, the police or public prosecutor can keep the person in custody, but a judge must step in before that time runs out.
Who decides if an arrest warrant (mandat d’arrêt) is issued?
The investigating judge makes the call after questioning the suspect to determine if there are enough grounds to issue an arrest warrant, which officially starts the preventive detention process.
What reasons can justify preventive detention in Belgium?
The law states that preventive detention is only permitted when it’s absolutely necessary for public safety, such as the risk of flight, the potential for reoffending, the destruction of evidence, or putting pressure on victims or witnesses.
Can someone be released from preventive detention on conditional terms?
Absolutely. A judge can grant conditional release, which may come with requirements like having a stable address, avoiding certain people, undergoing treatment, or regularly checking in with the police.
How does release on bail work in Belgium?
The judge may set a financial amount (cautionnement) that the accused must deposit with the Caisse des dépôts et consignations. If the accused complies with all procedural obligations, the bail is refunded at the end of the proceedings.
Is it possible to appeal the decision to maintain preventive detention in Belgium?
Yes. Decisions of the Council Chamber can be appealed before the Indictment Chamber. Afterwards, an appeal to the Court of Cassation is possible if it is believed that the law has been incorrectly applied.
What rights does a person have during preventive detention?
The law guarantees essential rights such as assistance from a lawyer, access to the case file necessary for the defence, the right to be informed of the reasons for the detention, periodic judicial review, and the possibility of requesting conditional release or bail.
What happens if the detainee does not comply with the conditions imposed by the judge?
Failure to comply with the conditions may result in the immediate revocation of provisional release and the issuance of a new arrest warrant. Compliance with these conditions is monitored by the police and judicial authorities.
Can I request that the arrest warrant be lifted?
Yes. Article 25 of the law allows the investigating judge to lift the arrest warrant if they consider that the grounds justifying preventive detention are no longer present.
