More about Marengo: The Bunker, the recusal procedure and the crown witness

Joost Nan

On Tuesday, 27 February, the Amsterdam district court handed down its verdict in the much-discussed Marengo trial. Various prison sentences were imposed on the seventeen suspects, including life imprisonment. The evidence in the Marengo trial largely relies on the statements of crown witness Nabil B. But how does the crown witness system work? And what might a possible appeal look like in this mega-process? Joost Nan, Professor of Criminal (Procedural) Law at Erasmus School of Law, explains more about the Marengo trial.

The Bunker

The Marengo trial was heard in the extra-security court the Bunker in Amsterdam-Osdorp. "That is where very serious criminal cases are heard, like the Marengo trial", Nan explains. The Bunker - originally an office building - is extra secured by heavily armed officers and military personnel. Previously, this special court also heard well-known cases such as the Passage trial and the trial of Willem Holleeder.

The Marengo trial is attracting enormous media attention. Does this also affect sentencing? "Media attention can play a role in several ways", Nan explains. "In a negative sense for the accused, the commotion of a sentence in the media can lead to a higher sentence because society is shocked. But a lot of media attention can also lead to a lower sentence because all the coverage was already objectionable for the defendant, and he has already been partly 'punished'." The Amsterdam district court stated that although there was a lot of media attention for the Marengo trial, the defendants did not suffer as a result, and it did not lead to an unfair trial. 

The crown witness

The evidence in the Marengo trial relies mainly on the statements of crown witness Nabil B., who was involved in the criminal organisation's ins and outs. How does this crown witness procedure work? "The statements of a co-defendant are used as evidence against other co-defendants. The crown witness thus cooperates with the investigation and normally, in return, receives a hefty sentence reduction for his cooperation", the Professor of Criminal (Procedural) Law explains. Nabil B. agreed with the Dutch Public Prosecution Service to make statements in exchange for a reduction in sentence. Instead of twenty years imprisonment, the prosecution demanded ten years. The court went along with this demand. Nan: "Only in very serious cases is such a deal made with a criminal witness".

The use of crown witness Nabil B. caused a lot of commotion. Nabil's lawyer, Derk Wiersum, his brother and his confidant, Peter R. de Vries, were liquidated. "The method does come under scrutiny partly because of that", Nan says. "At the moment, expansion of its scope is still under consideration. Especially the security of crown witnesses and the professionals and people around them will have to be adequately guaranteed."

The recusal procedure

The filing of several judicial disqualifications, or recusal, extended the duration of the Marengo trial each time. "If a defendant, or the prosecutor, feels that the judge is biased and does not give him a fair chance, a recusal request can be filed", Nan explains. "Other judges then go into a so-called recusal chamber (Wrakingskamer) to see if there is indeed an indication that the judge is biased". A new judge will be assigned if the recusal chamber agrees with the request. If the request is rejected, the court's composition will remain the same.

According to Nan, such a challenge is rarely effective. "Indeed, the Supreme Court's established principle is that a judge must be presumed impartial by appointment. This is only different if exceptional circumstances indicate that the judge is biased against the defendant or that the defendant's fear of this is objectively justified."


The Marengo trial took as many as 142 session days, spread over six years. This is not surprising given that the case had seventeen defendants and covered multiple serious offences. But what might a possible appeal look like? Nan: "The appeal could go on for a very long time. That could certainly be the case if the defendants still come up with all kinds of requests for investigation. In my inaugural lecture last summer, I argued that only investigations that could not or did not reasonably have to be requested at first instance should be conducted on appeal."

Chief Public Prosecutor Janneke de Smet says the Public Prosecution is also after Ridouan Taghi's financial gains. Nan explains that the most obvious way to do this is through the so-called 'plukze legislation'. Through this legislation, criminal profits can be taken away. "Then there will be a separate follow-up procedure to deprive unlawful gains", he says.

Prosecution of Inez Weski

On Tuesday, 27 February, De Smet said that the Public Prosecution will prosecute lawyer Inez Weski for participation in a criminal organisation. Weski conducted the defence for Ridouan Taghi for a long time. "Her case should really be separated from the Marengo trial", Nan stressed. "I think she should not be seen so much as a part of those individuals and their organisation."

But what exactly is Weski suspected of? "Participating in a criminal organisation means participating in a structured alliance, which aims to commit crimes. You then belong to the organisation and have a share in or support conduct aimed at or directly related to achieving the organisation's objective - the commission of crimes."

"It is not excluded that a lawyer participates in a criminal organisation, but in principle, of course, it is not the case", Nan says. A lawyer assists his client, and regular lawyer work falls outside the scope of participating in a criminal organisation. The right to lawyer-client privilege applies then; communication between lawyer and client is secret and must remain so. A litigant can thus have conversations with a lawyer in complete confidence without this information falling into the hands of third parties.

"But if a lawyer performs unusual acts and services, there may be a criminal offence. Under very exceptional circumstances, the lawyer-client privilege can then be broken, or the privilege does not apply to manual and clerical services", Nan says. "I do not know the case well enough, but Wezki may have been forced to step out of line due to severe pressure. She would not be the first. In that way, she could have participated in her client's organisation."

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With his inaugural address on 7 July 2023, Joost Nan officially assumed his position as Professor of Criminal (Procedural) Law.
Joost Nan

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