In theory for NL one could argue this is already the case. Government internals are public (WOB / transparent government). When I was a civil servant we once shared data and code with a citizen, although more regularly shared are internal documents. Our government has to make informed and documented decisions (AWB - general public law) and no decision that has legal ramifications can be made without manual intervention (an example: even automatical traffic fines have a name / number of an attested civil servant that finalized the fine in the paper trail). So all ingredients are there. Suppose they use external models or tools, how could they ever substantiate their decision in court without giving quite a lot transparency to the court?

Now in practice .... Our IRS has had a discriminatory way of working in place where no-one involved had access to their own files (GDPR?!) and even judges were reluctant to order transparency in the following proceedings giving the IRS the benefit of the doubt. Ultimately this became a politican scandal and will take years to resolve. And in the paragraph above I would have argued that the basics considering any case should be easily available in as much as 8 weeks for every citizen...