Mmmm - I don't want to turn this into an argument regarding Police access to airfields and other private properties including your own home, but we need to be cognisant of the fact that Police are 'authorised officers' under numerous Act of Parliament and may access where they have a reasonable belief that an offence has taken place, about to take place, could take place etc.
Aditionally there are a number of Acts where search of cars, aircraft and personal bags is permitted -
" reasonable belief". There are numerous 'Prima Facie cases' presented to Courts where Police believed an offence was about or had taken place.
There is also pages of Case Law rulings on Police access being challenged and most would send you to sleep which I can attest to as a previous Court Prosecutor ..
'Mens Rea' whilst not evident in every aircraft owners mind, may in fact see them inadvertently stubble into committing an offence later inadvertently without guilty intent.
The Police in the above Forum members Post if questioned on their authority could simply delay departure and call on Federal Police or any other relevant authority. So my advice is respectfully advise them if you feel they may have driven into an area that could be dangerous.
Before becoming too defensive or challenging authority on tarmacs or other areas within Commonwealth circumscribe familiarise yourself - or simply don't challenge authority - with the COPAL Act.
This Act gives Police access - Note - Section 4 (1) provides that the laws of the State that are in force will apply in relation to each place in that State that is a Commonwealth Place.
And to even complicate things Rec Aus pilots will often find themselves on Local Government property at Council owned airports and I can guarantee that Police have access here. State airports and Council airports now come into the mix with the COPAL Act.
Note - Reasonable belief is not arbitrary arrest or detention Section 15 of The Crimes Act refers. Read also Article 9 (1).
ASIC or not if you have nothing to hide why complicate or challenge authority and if I can be bold enough to give a warning 'Don't'. Simply don't test or try your luck and I suggest don't do what is suggested above.
Police are smart enough to know if potential offenders say they have "nothing to hide" it usually translates to " it's hidden already" I just want Forum readers to understand not to accept or take opinion in Forums etc as gospel as it may be inappropriate or even misplaced bravado.
Back to the ASIC - it cost me five times the cost of my Drivers Licence and that along with delays in issuing are more of a concern to me.