"There is a difference between the law itself and how it works in practice," he said.
"There are thousands – if not tens of thousands – of breaches of the RMA every year, yet under 100 prosecutions a year."
Further, he said, every council had a different approach to prosecution.
"Criminal law can be a very effective deterrent as it can result in large fines and, in extreme cases, individuals being sent to prison, but it's also a very expensive and time-consuming process."
Some of the smaller councils would never consider taking a prosecution, he said.
"What it leads to is a system where there are not many prosecutions being undertaken, and a lot of variation between regions."
Using deterrence theory, Wright was exploring how well the current system is working to discourage breaches of the rules.
If rates of prosecution were low, he suggests the deterrent effect is also likely to be diminished.
As well, he planned to investigate the deeper question of whether it is even appropriate for RMA breaches to be called criminal offences.
Part of his doctoral research would involve looking at how other countries sanction breaches of environmental law and considering what alternatives may exist.
In work that may ultimately influence policy, Wright was also reviewing the history of the RMA and how its sanctioning regime evolved, and options for possible sanctions reform.
Environmental policy analyst Dr Marie Brown, of The Catalyst Group, said fewer than 100 prosecutions across 78 agencies was "undeniably minimalist" - and the barriers to prosecution were numerous.
"This warrants investigation and this research looks really interesting," she said of Wright's study.
"I would suggest part of the underlying issue here is that some people regard impacts on the environment as the norm and think the idea of criminal culpability is almost nonsensical.
"That's more about people not regarding the environment as being very important, than the punishment necessarily being inappropriate."
But impacts on the environment could have significant immediate through to inter-generational impacts, said Brown, who canvassed the issues in her book Last Line of Defence.
"It is certainly true that prosecution can be time consuming, particularly so if the council is poorly resourced or does it only infrequently.
"There is a need for further assistance in the short term for councils to do the job of implementing the tougher sanctions, they have enormous deterrent value where they are applied."
Many councils did not do much in the way of enforcement, because it was "simply not politically desirable to prosecute your constituents", so enhancing the performance of some councils as credible regulators was essential, she said.
"Longer term, a good look at the institutional arrangements is probably needed in addition to on the ground improvements such as better training and more robust monitoring and oversight from the ministry and other central government departments."
Environmental Defence Society chief executive Gary Taylor felt there was a need for a dedicated, independent national enforcement agency.
"This could be the Environmental Protection Authority, with expanded governance, powers, obligations and resources."
The Government is seeking to address compliance woes with a new RMA oversight unit.
In announcing $3m in funding for it last month, Environment Minister David Parker acknowledged compliance, monitoring and enforcement actions was "somewhat variable" across councils.
Parker was overseeing a wider reform of the RMA which would consider changes requested by councils themselves, such as extending the limitation period for prosecutions from six months to 12 months.
Most of the bigger changes on the cards were still to be put before the Cabinet, but the Government was already pushing ahead with a series of smaller-scale reforms over the next year.
