Acting Prime Minister Bill English is playing down the fears of Maori Party MP Rahui Katene that new DNA sampling laws will bring young Maori into conflict with the police.
The Criminal Investigations (Bodily Samples) Amendment Bill was passed by Parliament under urgency on Wednesday by 108 - 13 votes. It will be phased in over the next two years.
Only the Maori Party and the Greens voted against it.
Mr English says DNA sampling is a potent weapon in the fight against crime and the police are keen to expand its use.
Labour's Maori affairs spokesperson says Maori concerns about the sacredness of body samples is outweighed by the need to give the police the tools they need to fight crime.
Parekura Horomia told Waatea News that DNA sampling will protect Maori from bad courtroom practice and decisions.
Mr Horomia says many young Maori get poor service from legal aid lawyers and end up pleading guilty to crimes they did not commit.