The vehicle owner was taken to Waitakere Hospital with moderate injuries but was later discharged.
University of Auckland law expert Bill Hodge said Police will first need to determine the cause of the man's death and if it was medical before deciding their next steps.
"Once you get past the first step which is cause of death then you say was he simply defending the chattel or had it shifted to self defence of himself as opposed to simply the vehicle."
Under one section of the Crimes Act, defence of movable property, a person could use reasonable force to protect their property but they could not cause bodily harm.
Whereas under a different section of the same law, a person is entitled to use reasonable force to protect themselves.
Wellington-based criminal lawyer John Miller said what could be classed as reasonable depended on the danger the person felt they were in at the time.
Police were unable to comment last night on whether any charges may be laid, but in an earlier statement said inquiries were ongoing.
Police are still trying to find the second man who left the address and are urging anyone with information about the incident to contact Waitemata Crime Squad on 09 839 0697 or Crimestoppers anonymously on 0800 555 111.
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