Given that most of Scotlands scum bags operate within the capital city and other built up areas, which are in CAS, you'll never have to worry as ATC will be fully aware of any such Police operation in the area, and if you are flying in CAS, you will do as you are told, thereby avoiding said wee timerous beasties.
Given that the trial is primarily concerned with searching for missing persons in the countryside or mountains or during marine searches, and the 'drone' is based initially in the Oban area, the above is misleading
It might be that they are deployed in more crime based activities if they are adopted for operational use after the trial, but I wouldn't expect to see them in Controlled Airspace during the initial trial period.