Social Development Minister Paula Bennett says an overhaul of social security legislation will not introduce any major reforms to the welfare system.
Ms Bennett announced on Wednesday that the Social Security Act, which came into force in 1964, will be rewritten. The Act underpins New Zealand's welfare system,
Ms Bennett said the Act has been tweaked so many times it is disjointed and difficult to understand.
She said the plan is to simplify the legislation, not introduce major reforms.
Ms Bennett said she did not expect the draft to be completed until late next year.
"It's got more amendments than the actual Act itself now ... It's unworkable, I think it is hugely increasing the workload particularly of front-line staff," Ms Bennett said.
The Act came into force in 1964 but parts of it reflect New Zealand's first social welfare legislation from 1938.
In the past 50 years there have been 139 amendments, and 186 sections have been repealed.
Ms Bennett said there could be some changes to the actual content but the overhaul was mostly a legal rewrite.
"We think we've done the major reforms. We're not looking at any major reforms with the rewrite - it is more about bedding in what we're already doing," she said.
Victoria University senior law lecturer Mamari Stephens said an overhaul of social security is long overdue.
Ms Stephens said the current legislation was messy, but that should not be used as a chance to reform social welfare by stealth.
"I know how difficult it is to understand and I can see how difficult it is to navigate...so part of me thinks it's a fantastic opportunity to come up with a piece of legislation that works a lot better than the current one does," she said.
But Ms Stephens was worried - despite Ms Bennett's reassurances - the new act would bring in policy changes under the radar.
"There's an awful lot of reform that can carry on around the edges there, so there's a little bit of worry here that there's going to be another tranche of reforms that could go on under the guise of creating a new Act."
Caritas, an aid agency, said thorough public consultation will be important when the Act is rewritten.
Spokesperson Lisa Beech said the current law was complex but it contained important principles and protections.
Amendments in 2012 were rushed through Parliament, and it was crucial the public was given enough time to have a say this time, she said.
"The first [2012 amendment], we only had 11 days for the community to comment on that through the select committee process... That's why we are concerned that we have a really full and thorough consultation process and a thorough assessment of the impacts it''ll have on vulnerable people."
Ms Bennett said there would be plenty of time for public consultation, with the draft rewrite not expected to be completed until late 2015.
An expert working group would be set up, and the Government had also asked benefit advocate groups to be involved, she said.