Rod Petricevic was previously refused parole after failing to show enough remorse for his crimes.

The Sensible Sentencing Trust is seeking a judicial review of the decision to release former Bridgecorp boss Rod Petricevic on parole.

The fraudster will walk free from prison on Monday, having served half of his six year and 10 month sentence.

The trust said the group had filed proceedings in the High Court at Wellington to try to overturn the decision.

Trust founder Garth McVicar said white collar criminals were in some respects worse than the likes of criminals who held up dairies.

"Many of those offenders have truly had terrible backgrounds, which might just provide an explanation for their offending, if not an excuse," he said.

Those like Petricevic came from privileged backgrounds, and had the benefit of good educations, McVicar said.

"To then go and rip off the life savings of trusting elderly people, as Petricevic has done, is utterly disgraceful conduct."

McVicar said elderly people who were victims of white collar criminals often died unexpectedly early, traumatised and broken.

"White collar criminals take note: You are in our sights, right beside the aggravated robbers and the bashers."

READ MORE: Bridgecorp boss Rod Petricevic granted parole

The action is being prosecuted by lawyers acting pro bono, including lead counsel David Garrett, a former ACT MP.

Petricevic was convicted in April 2012 of deliberately making false statements to trustees and distributing offer documents containing false statements while knowing the company was heavily in debt.

Bridgecorp owed $459 million to 14,500 investors when it was placed in receivership in 2007, and recoveries have been around 10 cents in the dollar.

Petricevic, 66, was previously denied parole after failing to show enough remorse for his crimes.

He told the parole board he would retire, and had no intention of offering advice or being involved in any business enterprise following his release.

Special conditions have been imposed that bar him from doing so.