Examiners for a check nominated by the authority

[slr737]

Quick question if someone can help me:

Here in belgium, the authority has to nominate the examiner who will take the exam, be it for a PPL check to the TRE check.

i was wondering if this was the same in other JAA country. And where that would be written in JAA or EASA documents.

i do not see the reason why the authority should nominate an examiner as long as the examiner you take follow the rules such as no training given (or max 25%)

thanks for the help