The Justice Minister's plan to ensure dangerous criminals deported from Australia can be supervised when they return to New Zealand could cause new problems, warn lawyers.
The two countries yesterday signed an information-sharing agreement, which will provide agencies here with up to six months' notice of any planned deportations.
Justice Minister Amy Adams wants to take things further, saying officials needed to be able to treat the offenders as if they had served their sentence in this country.
She said authorities could currently seek things like an extended supervision order, if the offender was at the most extreme end of the risk scale, but she said they needed to be able to monitor the offenders more effectively, and place necessary restrictions on them.
But the head of the Criminal Bar Association said he foresaw problems with the potential law change.
Tony Bouchier said there could be huge logistical issues in enforcing this.
"What would happen if there was a breach of parole and a person denied that breach of parole? I can foresee huge legal problems and expense in trying to enforce Australian court sentencing regimes."
Defence lawyer Steve Bonnar said any law change needed to ensure it did not penalise offenders twice.
Mr Bonnar said a new law would be a balancing act, and although public safety needed to be taken seriously, so did civil rights.
"There needs to be a proper recognition, first that people are not effectively being double-penalised for their acts in another country, so someone subject to the laws in another jurisdiction has been treated, we don't generally penalise them again when they return to this country."