Jacinda Ardern says the Immigration Minister was rightfully constrained when deciding on the residency of a repeat drink-driver.

Iain Lees-Galloway gave residency to a person with several drink-drive convictions after previously giving residency to convicted drug smuggler Karel Sroubek.

The Prime Minister says a tribunal had already protected the person from deportation.

She told Mike Hosking the minister didn't have the power to overrule that protection, and that's the way it should be.

"There are situations where it’s absolutely right we don’t intervene.

"We should not come in and put a political overlay on decisions which are made through the justice system."

Ardern says a tribunal had ruled the person couldn't be deported, and the minister made his decision on that basis.

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