In a judgment dated 14 February 2019, the Constitutional Court has significantly narrowed down the scope of the principle of res judicata in criminal matters. Following this ruling, from now on, a definitively convicted defendant who has been able to defend himself before the criminal court will be able to rely, in a subsequent civil trial, upon proof of his innocence provided by a party that was not involved in the criminal proceedings. With this ruling, the Constitutional Court has further extended the tendency set by the Court of Cassation, narrowing down the scope of the principle of res judicata with a view to protecting the rights of defence.

The authority of res judicata in criminal affairs in relation to the civil judge

The authority of res judicata in relation to the civil judge refers to the principle according to which the civil judge, when assessing an action brought before him, is bound by what has previously been decided by the Belgian criminal judge in a final judgment on the merits of the case. This principle has long been recognised as a general principle of law designed to ensure the unity of jurisprudence: two rulings in the same dispute may not contradict each other. The legislator's choice to give priority to criminal judgments is justified because of the public-order nature of criminal law.

For example, if a defendant was convicted in a criminal court for driving while uninsured, he could not claim in subsequent civil proceedings – or at least not successfully – that he did have insurance.

The limitation of the erga omnes nature of the authority of res judicata by the Court of Cassation

Traditionally, it was held that the principle of res judicata in criminal affairs had effect erga omnes. Since criminal proceedings are conducted on behalf of as well as in the interests of society, these decisions have the force of an irrefutable presumption which is imposed on everyone, even on those who were not involved in the criminal proceedings. 

However, the Court of Cassation has gradually abandoned this erga omnes characterisation with a view to protecting the rights of defence (Article 6(1) ECHR). The first judgment that initiated the erosion of the erga omnes characterisation was the well-known Stappers judgment of 15 February 1991. In this judgment, the Court held that when the rights of defence of a third party, who was not a party to the criminal proceedings, are being compromised, the third party can, in a subsequent civil procedure, call into question a matter of facts which had been finally settled by the criminal court. The Court of Cassation confirmed this exception in judgments dated 2 October 1997, 24 June 2002 and 23 September 2004.

Following these judgments, it was now established in cassation case law that the authority of res judicata does not prevent a party from calling into question the information derived from criminal proceedings in a subsequent civil trial, but only insofar as that party was not a party to the criminal proceedings or did not have the opportunity to freely defend his interests there. This jurisprudence was marked as a limitation to the existing erga omnes characterisation of the authority of res judicata.

For example, even though a defendant is acquitted for arson, the insurer – who was not a party to the criminal proceedings – should still be given the opportunity to prove, in subsequent civil proceedings in which he is summoned to pay compensation for the damage caused by the fire, that the insured caused the fire intentionally.

Therefore, a distinction was made: the absolute authority of res judicata was limited for third parties to the criminal proceedings (such as the victim who was not a party during the criminal proceedings and the insurer or party with civil liability for the defendant who were not involved in the criminal proceedings), while it still remained in full force for the parties who had been able to present their defence before the criminal court.

The Constitutional Court takes things one (big) step further

In its judgment of 14 February 2019 (no. 24/2019 (only available in Dutch and French), the Constitutional Court took one (major) step further in limiting the authority of res judicata. The Court ruled that the authority of res judicata was also not absolute in relation to a convicted defendant who did have the opportunity to present his defence before the criminal court. According to the Constitutional Court, a definitively convicted defendant, regardless of whether he had been able to defend his interests before the criminal court, should still be able to benefit from proof of his innocence provided by another party that was not involved in the criminal proceedings.

Thus, for the first time it was established that the authority of res judicata is no longer imposed as an irrefutable presumption, even with regard to the parties who have been able to present their defence before the criminal court.

The Constitutional Court ruled that it is a logical step to apply the limitations to the authority of res judicata to all parties to the civil proceedings, including the defendant who has already been able to defend his interests before the criminal court. According to the Constitutional Court, any other interpretation would be contrary to the principle of equality and the right to a fair trial of the defendant involved in the same civil proceedings.

If a "third party to the criminal proceedings" provides evidence which refutes elements derived from the criminal proceedings, the parties who were also parties to those criminal proceedings, and who have been able to defend their interests there, should still be able to benefit from this evidence.

Suppose, for example, that a person is convicted of involuntary manslaughter. In a subsequent civil trial, the insurer will intervene with the purpose of providing proof of the absence of any causal link between the death of the victim and the actions of the accused. Taking into account the aforementioned judgment, the defendant should be able to benefit from the proof provided by the insurer. Consequently, the definitively convicted defendant can then no longer be ordered to pay compensation to the victim, since he will be able to rely on the exculpatory evidence provided by the "third party to the criminal proceedings".

In short, the possible restrictions to the authority of res judicata resulting from  the Constitutional Court's judgment of 4 February 2019 have been substantially increased.