Abstract
By the time it was formally signed by New Zealand in February 2016, the Trans-Pacific Partnership Agreement (TPP) had morphed from an unassuming regional bargain into a mammoth agreement embracing some 40 per cent of global GDP and one third of world trade. The effects of the TPP, and whether those effects are desirable, are subject to fundamental disagreement within Parliament and wider society. Recognising that the final prospects for the instrument’s entry into force remain mired in United States domestic politics, this article is not principally concerned with supporting or opposing New Zealand’s ratification of the TPP. It instead interrogates the instrument’s constitutional meaning by examining the challenge that investment treaties pose for traditional accounts ofNew Zealand’s constitution. To do so, we develop what we term a “globalised constitutional realism ”approach; combining the insights of “new constitutionalism ” with the “constitutional realism ” method of analysis advocated by Matthew Palmer. We then explore three different constitutional effects that entering into the TPP may come to have: broadening a parallel form of adjudication; introducing a wide-ranging takings doctrine; and constraining Parliament ,’v legislative capacity. Finally, we conclude our discussion with some thoughts on the overall legitimacy of these changes to New Zealand’s constitutional ordering.