A man who successfully had his name removed from the sex offender register has gone to the High Court to get himself taken off it for a second time.
The man, who has name suppression, was released from prison in June last year and the post-sentence conditions imposed on him by the Parole Board had expired when he was placed on the register.
In November he appealed against the decision to register him and the Police Commissioner revoked his registration.
Last month, the government acted under urgency after it became clear the legislation establishing the register was flawed, with loopholes allowing some sex offenders to escape being on it.
The man's name was subsequently re-entered on the register.
However, his lawyer, Douglas Ewen, told the High Court in Wellington today the amendment was a constitutional affront pushed through Parliament in just one day.
He said the change should not apply to those who had already successfully had their sex offender registration revoked.
"There are very strong presumptions at common law and under the Bill of Rights Act that legislation will be construed narrowly when it is retrospective.
"And there will be a positive presumption against it robbing a successful party of the fruits of their litigation challenge."
Mr Ewen said the legislative change was a flagrant breach of the Bill of Rights and there was no provision in the legislation for re-registration of someone who had been removed from the register.
However, Crown lawyer Austin Powell said the amendment to the register was properly implemented.
He pointed to the separation between the roles of Parliament and the courts.
"The court has always seen its primary role as upholding primary and fundamental rights and legality.
"But where the court has done that it has always done so with immaculate respect for the separation between the branches of government."
Mr Powell said Parliament was entitled to sit under urgency. It did so and the bill was passed with royal assent.
Justice Faire reserved his decision.