Police paid out Clint Rickards' contract last year in a $300,000 resignation deal that also had the effect of stopping disciplinary charges against him.
The money represents 13 months' salary - from the date he resigned up until next month, when his contract would have ended.
Louise Nicolas, whose rape allegations against Mr Rickards and two high-profile former police officers led to court trials, said the "golden handshake" could have helped countless people and crisis centres.
The payment, which does not include superannuation, brought to more than $750,000 the amount Mr Rickards was paid from the time he was stood down on full pay in February 2004 after sexual misconduct allegations were made against him.
Police told the Herald yesterday that Mr Rickards, who was an assistant commissioner, was paid $210,000 in salary entitlements plus $90,000 in leave entitlements after resigning in November 2007.
Mrs Nicholas told the Herald she was surprised by the amount.
"An extra $300,000 is just unbelievable. And I'm extremely disappointed he was able to walk away from those disciplinary charges."
She said she hoped he hadn't been paid to go away. He brought disrepute on the police and the disciplinary process should have run its course.
"I accepted that he was entitled to his superannuation because he resigned and I accepted that he was entitled to his full salary while he was stood down.
"But what I don't accept is this extra $300,000.
"That is like that golden handshake that I hoped he wouldn't get.
"You wouldn't believe how many crisis centres and how many people that $300,000 would help," said Mrs Nicholas, who works for Rape Crisis.
Police released the information almost one year to the day after the Herald requested it under the Official Information Act.
The police had refused to divulge the information, claiming privacy interests outweighed the public's right to know, but Chief Ombudsman Beverley Wakem agreed with the Herald that the weight of public interest in this case involving a position of high public office and significant public money warranted release.
During the time he was stood down on full pay, Mr Rickards completed a law degree.
The New Zealand Law Society this month granted him a certificate of good character, clearing the way for him to practise law.
Mr Rickards said he thought the payment was not excessive given his 28 years in the police and the high rank he reached.
"I probably could have stayed on and probably fought the fight but the priority for me was my family," he told Radio Waatea.
"It [the resignation payment] was something that I decided to take that was sufficient to allow me to finish my degree and sufficient now that hopefully I can progress."
Mr Rickards said he was interested in practising in Treaty, Maori land and employment law.