"It's a remarkable state of affairs," he said.
"It seems the Government was hoping the Supreme Court would rule in Corrections' favour. They chose to roll the dice and lost. It's not rocket science, of course affected prisoners should be compensated it's only fair to do so."
Senior Tauranga defence lawyer Bill Nabney agreed.
"How would you feel if you spent even one extra day in jail than you should have. Of course there should be compensation."
Tauranga criminal barrister Peter Attwood said it was a question of fairness, and holding a government department accountable for what was clearly a systemic failure.
"The reality is that, should affected people not be compensated, then it would really create an issue of angst for those who have been illegally detained and further alienate the public."
Ken Evans, Tauranga spokesman for Sensible Sentencing Trust, said the question of compensation was not something the trust would comment on.
"The Sensible Sentencing Trust believes that prisoners should serve every day of their sentence given by a judge before they are released, " he said.
Prime Minister John Key said it was "very uncertain" whether compensation should or could be paid.
Legislation that would block compensation claims from prisoners who spent too long in jail was possible, Mr Key said.
"It's a possibility, but I wouldn't say necessarily a probability at this point," Mr Key said
Retrospective legislation that would remove any obligation to pay compensation was yet to be considered.
The Parole Act
The Parole Act 2002 specifies how and when offenders are released from prison. It also set up the New Zealand Parole Board whose main functions are to make decisions about the release of offenders on parole and to set release conditions for offenders released on parole or at the end of their sentence.