Police powers and Responsibilities act keeps getting changed, but not in the area's you'd be worried about. Its pretty big so your better off just looking at sections. I can summarise it for you if you want....the police were the ones to create this act and they drafted it for parliment. Short story, they get to do pretty much anything they want and you have to contest or sue if you dont like it, however the law is usually not in your favour.
Second the l/p plate changes are on the site below, they have been approved and are coming to qld. http://www.transport.qld.gov.au/qt/LTASinf...ers_diagram.pdf