ACT Party law and order spokesperson David Garrett has admitted in Parliament he used the name of dead child to get a passport after being inspired by the thriller The Day of the Jackal.
It was revealed this week that Mr Garrett has an assault conviction following an incident outside a bar in Tonga in 2002.
On Wednesday, he told Parliament that in 1984 he used a method described in the Frederick Forsyth novel about a professional assassin to obtain the birth certificate of a dead child born around the same time as himself. He then obtained a passport in the child's name.
Mr Garrett said he could not explain his actions, other than he was curious to see if the method would work.
The MP told the House the passport expired without ever being used, but in 2005 he was arrested, along with a number of others, following a police inquiry into passport fraud sparked by the conviction of Israeli citizens believed to be Mossad agents.
Mr Garrett says he admitted obtaining a passport under false pretences, was discharged without conviction and also got name suppression.
The MP is already under fire for not publicly disclosing the assault conviction. He said he kept this secret because he is innocent of the charge but acknowledged many convicted offenders say they are not guilty of the offences they are charged with.
Mr Garrett, a list MP and former legal adviser to the Sensible Sentencing Trust, fronted ACT's three-strikes legislation.
The Labour Party says Mr Garrett looks like a hypocrite for advocating tougher sentences for criminals.
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Hide admits conviction for being drunk
ACT Party leader Rodney Hide on Wednesday also revealed that he has a past conviction.
Mr Hide told Television New Zealand's Close Up programme that, as a young man, he worked on North Sea oil rigs and was arrested and convicted for being drunk at London's Heathrow Airport.
"A bunch of us guys had too much to drink (and) got into trouble. I didn't assault anyone, but I got arrested and I got charged when I was a very young man.
"Am I proud of that? Not at all - I'm pretty ashamed."
Mr Hide said like him, Mr Garrett worked on oil rigs and had a hard life.
He said what Mr Garrett has done with the passport fraud is "horrific" but backs him as a candidate and MP for ACT.
Mr Hide said Mr Garrett told him about the assault and passport fraud before he joined the party in 2008, but was not concerned because they were minor incidents.
He said many people - including himself - have done things in the past they are ashamed of.
Name suppression not supported
The head of the Sensible Sentencing Trust does not agree with David Garrett getting name suppression over his passport fraud case.
Garth McVicar told Checkpoint on Wednesday the trust supports a total open and honest court system, and does not support name suppression.
Mr McVicar said he is disappointed Mr Garrett did not take the first opportunity to stand up and be open with New Zealanders in his opening address in Parliament.
He says he hopes Mr Garrett will learn from his mistakes.
Listen to Checkpoint interview with Garth McVicar