A lawyer who previously represented a key witness in the Marengo trial has received a disciplinary warning for professional misconduct. Bart Stapert, now a judge, was found to have acted improperly by confirming information to the Public Prosecution Service (OM) without consulting his former client, Nabil B., the crown witness.

The Board of Discipline determined that Stapert should have recognized that Nabil B. might have a different perspective on the matter and should have consulted with him before communicating with the OM. The specific issue involves whether agreements were made regarding the deduction of a seven-month prison sentence for firearm possession from Nabil B.’s final sentence. Nabil B. claims such an agreement existed as the arrest was staged in consultation with the OM.

Stapert denies recalling any such agreements, which seems to contradict a handover document from 2018 where he mentioned that “it has been agreed that the time will be deducted” at a later time. Nabil B. filed a complaint in 2022 accusing Stapert of carelessness, improper case transfer, and violating confidentiality.

While most of the complaints were deemed time-barred, the disciplinary board upheld the complaint regarding Stapert’s communication with the OM in 2021. The warning was issued despite Stapert’s “clean disciplinary record” and the “special situation” of being under intensive security since assisting the crown witness.

The ruling was initially withheld from publication due to security concerns related to the Marengo trial, which involves multiple murders and attempted murders. However, it was later published, extensively anonymized, after inquiries from de Volkskrant.

Stapert has stated that he has “no comment” on the ruling and that the case is being appealed to the Court of Discipline. Peter Schouten, Nabil B.’s current lawyer, confirmed the appeal but declined further comment.

Schouten also highlighted a document alleging that Nabil B. believes Stapert prioritized the interests of the OM over his own and did not negotiate the crown witness deal aggressively enough. The document also reveals that the OM urged Nabil B. to withdraw his complaint against Stapert, raising questions about the OM’s interference in the matter. The OM has declined to comment on these questions.