This is apparent from documents that NOS viewed after they were requested under the Public Access Act (WOB).
Discussion
Prior to the mask obligation, a considerable discussion was held behind the scenes about who should enforce. The police refused to act against people who would not wear a mouth-nose mask on public transport.
There was a dispute within the government for weeks about who should enforce and how that should be done. Lawyers did not agree in which law the mouth mask obligation should be included: the Passenger Transport Act or in the corona emergency regulations (and later emergency law). This determined to what extent action could be taken and whether not only special investigating officers (boas), but also agents could be enforced.
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