A Malaysian diplomat who left the country with immunity after being charged with sexual assault did not have a diplomatic passport.
But Foreign Affairs officials say Muhammed Rizalman bin Ismail was still entitled to immunity because of his diplomatic status.
New Zealand has filed an extradition order for the 35-year-old diplomat, who was charged with burglary and assault with intent to rape in May after allegedly attacking a Wellington woman in her home.
Rizalman, a second warrant officer at the Malaysian High Commission in Wellington, fled the country two weeks later after a misunderstanding between New Zealand and Malaysian officials.
Yesterday, the Ministry of Foreign Affairs and Trade confirmed that Rizalman travelled to New Zealand on his own Malaysian passport.
But a spokeswoman said he was "entitled to immunity from criminal jurisdiction under the Vienna Convention on Diplomatic Relations".
Prime Minister John Key reaffirmed Rizalman's right to leave the country despite facing criminal charges.
"He is, because of his diplomatic status in New Zealand, able to claim immunity and that was the position that the Malaysian authorities in New Zealand invoked despite the fact that New Zealand did not want them to do that."
Mr Key reiterated that he wished that the extradition process was progressing more quickly.
He said he signed the paperwork for the extradition order while he was caretaker Prime Minister after the election, "which was a step faster than some people might expect me to".
The delays are a result of the legal complexities of the case. New Zealand does not have an extradition treaty with Malaysia, and officials in both countries are working to build a case before an arrest warrant is issued for Rizalman in Malaysia.
Rizalman's alleged victim, Tania Billingsley, has criticised the Government for its handling of the issue, in particular for allowing Rizalman to leave the country.