And playing devils advocate for the moment, is it possible that CASA was instructed to continue as 'ops normal' in thier dealings with this guy whilst the police investigation was happening in the background?
Renewing an AOC of a known felon is not "ops normal". The Act prohibits CASA "facilitating" illegal acts during the investigation. It would be the same as the Cops lending a robber a gun so he could be caught committing further illegal acts.
CASA admits they knew he operated "without a licence" between 2012 and 2016 (what ever that means) and other illegal acts including aircraft overloading but took no action and renewed his AOC for four years in December 2016, two months
after it has been confirmed they were involved in the investigation.
No doubt CASA owes Australia a detailed explanation?