Prime Minister John Key says officials will look at whether the rules for granting a foreigner residency need to be toughened up in the light of the Kim Dotcom case.
Mr Dotcom - a German citizen - is at the centre of one of the world's biggest internet piracy prosecutions.
He was granted New Zealand residency under an investor category in 2010 despite a fraud conviction.
A year later, the Overseas Investment Office turned down his request to buy the Coatesville mansion he has been renting.
Mr Key says Mr Dotcom's conviction was not relevant under immigration rules because of Germany's clean-slate provisions, but it was considered relevant for the character test under overseas investment rules.
The Prime Minister says he's getting advice on whether there is a discrepancy in the regulations and whether the residency provisions should be tightened.