Proposed new welfare laws run the risk of discrimination, a parliamentary committee has been told.
The Human Rights Commission says there's insufficient evidence to justify imposing compulsory budget management on young beneficiaries.
Under the Social Security (Youth Support and Work Focus) Bill benefit payments can be made through cards that can only be used for accommodation and food, with a small cash-in-hand allowance.
Chief Human Rights Commissioner David Rutherford told the social services select committee on Friday "the evil of discrimination" had to be avoided unless it could be justified and he didn't think in this case that it was.
Deputy Children's Commissioner Jo Cribb said in her submission there must be monitoring to assess the impact of the proposed new welfare regime on young mothers and children.
The bill delivers payments for childcare while it imposes new work obligations on sole parents.
Ms Cribb said it was essential for childcare to be high quality and accessible - particularly for young mothers in remote areas.