The Law Society says the pace of proposed reforms to the justice system needs to be slowed down.
Justice Minister Simon Power told the University of Otago law faculty on Wednesday night he is not ruling out bulk funding legal aid for law firms.
He says the cost of legal aid has ballooned by more than $45 million in the past three years.
Mr Power also wants a change from the current adversarial approach in some trials.
He says children and other vulnerable participants in court should only have to give their evidence once and should not be subjected to aggressive cross examination.
Another proposal is making jury trials only for more serious offences.
Mr Power says the suggestions are not Government policy but change will happen with or without the support of the legal world.
Law Society criminal convenor Jonathon Krebs says it does not feel listened to.
Mr Krebs told Morning Report Mr Power's suggestions would fundamentally change the justice system and marginalise defendants' rights.
He says some changes seem to be motivated by cost-cutting.
University of Auckland associate professor of criminal procedure Scott Optican is also warning about the speed at which the minister is moving.
Dunedin lawyer Tim Black says Mr Power needs to back up what he is saying with clear evidence that there is actually a problem.
Mr Power says he will take a paper to Cabinet in November recommending the changes.