It blamed the act for consents being declined, but he said many of them did not stack up for other reasons. Changes to the RMA could stop people having input into what happened around them.
"Everybody wants things to be less bureaucratic, and everybody wants to be able to have a say when things affect them."
Auckland's housing situation was different from the rest of the country's, he said.
"Should the Auckland urgency that they're always on about be used as an excuse to change things in other parts of the country?"
The RMA was better than the law that preceded it and lots of case law had built up around it. Changing it would create a "field day" for lawyers, who would build up new case law.
The new slant proposed would put economic growth before sustainability, and sustainability was more important, Mr Beautrais said. "Environmental sustainability is what everything else is built on."
Major pieces of legislation like the RMA should be changed seldom, and had to be done right. They needed agreement between political parties.
"We wouldn't want a bare majority of National and Act shoving through something that's one-sided."
He said people needed to look at both sides of the matter.
"People will need to have a good close look at what's proposed and be given lots of time to make submissions and those submissions should be taken very seriously."