The Law Society is urging the Government to drop plans to give itself extraordinary powers to change the Resource Management Act in order to establish "special housing areas" intended to fast track affordable housing.
The Housing Accords and Special Housing Areas Bill being considered by a parliamentary committee would enable the Government to strike "housing accords" with councils to streamline the planning process and quickly free up land for new housing.
However, in a stinging criticism of the proposed legislation, the Law Society said parts of it were "contrary to the rule of law and good legislation principles".
The society was particularly concerned that the bill would allow the Government to make changes to the Resource Management Act - the key legislation governing the planning and consenting process for councils - without having those changes considered by Parliament.
Under clause 88 of the bill ministers would be able to make regulations - which do not require full parliamentary scrutiny - to alter parts of the RMA.
"The scope of these regulation-making powers is very wide," the society's Chris Moore said.
He pointed out the 2008 Cabinet manual which ministers work under specifically warned against regulations "that purport to amend primary legislation" like the RMA.
"The Law Society submits that clause 88 is undesirable and should be removed."
The society also criticised other aspects of the bill and its hurried passage through Parliament. The legislation was introduced under urgency with last month's Budget, with the Government only allowing 10 working days for consultation and submissions.
"The rationale for using urgency is not clear," the society told Parliament's social services committee this week.
Labour's housing spokesman, Phil Twyford, said clause 88 gave the Government the ability "to make it up as they go along without having to come back to Parliament".