Greens co-leader Metiria Turei has confessed she sub-let her home and lied to Work and Income, as a single mum claiming benefits.
Ms Turei made the astonishing admission at her party's conference, launching a new welfare policy package.
"I knew that if I told the truth about how many people were living in the house my benefit would be cut. And I knew that my baby and I could not get by on what was left.
"That was what being on the benefit did to me - it made me poor and it made me lie."
Ms Turei said it was a "stressful and terrifying experience" and knew she could be charged with fraud at any moment.
She had lived in five flats with her daughter Piupiu, while completing a law degree, and had extra flat mates paying rent in three.
The confession was designed to highlight "holes" in the welfare system.
In its new families package the Greens have pledged:
- To raise all core benefits by 20 per cent.
- Increase the amount people can earn before their benefit is cut to $200 a week.
- Introduce a $72 a week Children's tax credit for 178,000 kids in households where the income is below $44,800.
- Remove financial penalties and "excessive" sanctions such as work testing.
The Greens also want the top tax rate hiked to 40 per cent for those earning more than $150,000, and reduce the bottom rate to nine per cent for those under $14,000.
The package would cost $1.48 billion and fits within spending limits set under an MOU with Labour.
The Greens say a single mum, not in work, with two kids would be $180 a week better off, and a two parent family, with two kids and one parent earning the median income would have an extra $105. T
The same family - but earning over $70,000 would get $88.
Ms Turei told around 300 Green supporters: "The safety net is torn. More and more people are falling through...we will not be a Government that uses poverty as a weapon against its own people."