A career criminal battling against a prison smoking ban could pave the way for inmates to get compensation.
Arthur Taylor has spent months fighting the ban, and late last year the High Court ruled in his favour finding it invalid and unlawful.
But the Department of Corrections says new regulations it put in place, making tobacco contraband, overrides that ruling.
Taylor has been back at the Auckland High Court this week arguing his case, but he can't actually get the ban on smoking lifted as the new regulations have tightened up the law.
But because the new rules were only validated in parliament in February this year, Taylor is arguing that any enforcement of the ban from when it was introduced in July 2011 to last month was illegal.
If the judge rules in his favour, it could mean any prisoner who was punished for smoking during that 18-month period could seek compensation.
The judge has reserved his decision.