Not sure who is responsible for confirming whether he had a permit: oversees seller or shipping company, or customs/import upon receipt in Australia.

Guardian article says, "he ordered the items from a US-based science website and they were delivered to his parents’ home.... Nuclear materials can be imported legally by contacting the Australian Safeguards and Non-Proliferation Office for a permit first."

So maybe all of this fuss was due to not having applied and received a permit?