This was echoed by the University of Canterbury's director of criminal justice and senior lecturer Jarrod Gilbert when he stated:
"I have certainly heard about this, mostly when I was travelling with the Justice Advisory Group.
"I have no doubt that this issue is real."
The figures relate to defendants whose judicial outcomes were classed as "other proved", meaning they were not recorded as convictions with the police offering diversions or discharge without conviction under section 105 of the Sentencing Act 2002.
One man, who asked to remain anonymous, told the Herald of his experience last year.
He was held in custody on remand awaiting trial.
On the morning of his trial, he said he was coerced into pleading guilty to a lesser charge as he was warned by his lawyer, in no uncertain terms, that because of the demographics, race and gender of the jury, it was highly unlikely that they would find in his favour.
If this happened, he was told, he could expect to face a further 18 months behind bars.
If, however, he pleaded guilty to a lesser charge, because of the time he had already spent in prison on remand, he would be released in a matter of days or weeks as opposed to months and years.
Even though he was confident of being cleared of all charges, he found the prospect of imminent release too tempting and ended up pleading guilty to a charge he was adamant he had not committed, he said.
Jeffery said incidences such as this are not surprising,
"It is true that being on remand for lengthy periods often prompts a defendant to plead to reduced charges if they would be released soon," he said.
"At times, I am sure this results in defendants pleading guilty to things they didn't do, particularly in the domestic violence area."
These outcomes have judicial reform advocates questioning the ethical practices of prosecutors in the first place.
"One of the main reasons for defendants pleading guilty at a later stage is that the prosecutor has more of an incentive to reduce the charges/and or look at the evidence properly, the closer they get to having to prove the charges," Jeffery said.
"Basically, if you get to a point that the Crown/Police have offered to lower the charges, and therefore you get the benefit of a lower charge and full discount for guilty plea, and the Judge has told you what sentence you would get, then defendants often choose that certainty over the uncertainty of a trial and being found guilty and loosing discounts for guilty plea."
Crown Law's Executive Advisor to the Solicitor-General, Elizabeth Underhill, said that although there were instances of this happening, there were no ulterior motives from the prosecution,
"We disagree with Mr Jefferies' characterisation of the incentives for prosecutors, and the suggestion they systematically review files close to trial," she said.
"While we accept that on occasion a prosecutor might assess the detail and merits of a trial file later than is ideal, that is invariably the result of workload pressures and not systemic practice or a matter of ethical compromise.
"On other occasions it may be that further evidence comes to light, or there is some change of circumstances, close to trial which makes a plea arrangement appropriate when it was not previously."
