There is a renewed call for Immigration Minister Iain Lees-Galloway to resign over his handling of the Karel Sroubek debacle following a review of processes.
A report has found that in complex cases like Sroubek, decision-making powers should be given to immigration experts rather than ministers because they have more time and expertise.
It also says ministers should only step in as a last resort.
- Review into Immigration New Zealand's deportation process finds room for improvement
- Immigration Minister reconsidering Karel Sroubek residency decision
- Immigration Minister Iain Lees-Galloway reveals Karel Sroubek's residency conditions
The decision to grant drug smuggler Sroubek residency was made by Lees-Galloway last year in less than an hour and without reading the full file.
He was then forced into a skidding U-turn after it was revealed Sroubek had travelled back to his country on a false passport - information Lees-Galloway said he wasn't made aware of when he made his initial decision.
The minister said on Wednesday he's since made changes to the process that he uses.
But it's not good enough for National's justice spokesperson Mark Mitchell, who is now calling on the minister to resign.
Newshub asked the minister if he made the wrong decision, but he avoided the question, saying: "Karel Sroubek is liable for deportation."
A major review by Mike Heron QC into immigration processes released on Wednesday found the minister probably wasn't the right person to make the call in the first place.
"It makes sense to withdraw the minister from the fray."
Heron thinks immigration experts - with more time and knowledge - should be making those tough decisions.
"Obviously it makes sense in complex cases not only to have the right material, but the right advice, enough time and perhaps the expertise... all that package goes into the mix."
Mitchell said it should "still remain a ministerial responsibility".
He described it a "knee-jerk reaction because we've got a minister who's shown he's not up to this decision-making".
The minister relied on the summary of Sroubek's file to make his rushed residency decision, and that came as a surprise to officials.
The report says even the grounds in the summary were understood by most to be sufficiently powerful that the decision of the minister was unexpected.
Carolyn Tremain, chief executive of the Ministry of Business, Innovation and Employment (MBIE), said Sroubek "made the decision in absolute discretion and we don't question what he has decided".
The other key recommendation is for the minister to be able to request advice.
Heron suggested, "Perhaps more of a dialogue around complex or novel cases as Sroubek was, I think that would address it."
But immigration ministers can already do that - they can seek advice.
"Of course that's the case," Heron said.
Newshub asked Lees-Galloway why he didn't seek that advice.
His response, "I've made changes to the process I use."
Mitchell said he thinks the minister "should go".
But Prime Minister Jacinda Ardern has no plans to sack Lees-Galloway.
"These are complex cases - the report rightly suggests the process needs to change because Immigration New Zealand and the minister are carrying too much risk."