Brendon McCullum has called for Lou Vincent to be shown clemency during his delivery of the annual Cowdrey lecture at Lord's.
The Marylebone Cricket Club chooses one cricket identity a year to offer their views on the contemporary game. Martin Crowe is the only other New Zealander to be chosen, in 2006.
The Vincent revelation came as a tailender in McCullum's order of topics. The 34-year-old transition from advocate of gamesmanship to backer of sportsmanship, and his reaction to Phil Hughes' death were other highlights.
McCullum described Vincent's insight into the "dark and sinister world of match-fixing" as "invaluable" after he accepted responsibility for his match-fixing actions, acknowledged guilt and came forward to give court evidence about its practices.
He said while "loathing the fixing activities", Vincent was a "vulnerable character" and he admired his courage in giving evidence in Chris Cairns' perjury trial last year.
The jury found Cairns not guilty.
McCullum said Vincent "laid his soul bare at considerable personal cost". The cost was 11 life bans from the England Wales Cricket Board. McCullum struggled with the punishment's severity.
"While it was reported that Lou had agreed to the 11 life bans, I suspect that sitting in New Zealand without a dollar to his name, he was unable to do anything else. In the criminal law in New Zealand a defendant is given some clemency for co-operation and entering a guilty plea. It seems to me that Lou did not receive any such acknowledgement but, rather, had the book thrown at him."
McCullum's reason for raising the issue was to highlight the fact players who are approached to fix are generally weak and vulnerable, therefore need an incentive to come forward.
"I have no doubt that the ECB's severe punishment of Lou has robbed the game of a golden opportunity to have him provide education to players, something I feel could have made a difference in the future."
Elsewhere, McCullum spoke of his maturity in the sport.
He said he was "proud to be called brash, aggressive and perhaps even arrogant" in his early international years because a couple of teammates who he described as "heroes" had a "swagger and sense of entitlement".
"Did I want to be like them? You bet I did. I became incredibly competitive; winning was everything and I didn't really care what it took to win."
McCullum said he regretted those days. He used the running out of Sri Lanka's Muttiah Muralitharan at Christchurch in 2006 as his prime example.
"Kumar Sangakkara scored a magnificent 100 in the second innings. When Kumar reached his 100, Sri Lanka were nine down - the ball was still in the air being returned to me as wicket-keeper when Murali left his ground to congratulate Kumar... I removed the bails and appealed. Murali was given out and we went on to win."
McCullum belatedly apologised to Muralitharan and Sangakkara for his actions.
He also touched on a harrowing 2012-13 summer when he took over as New Zealand captain in controversial circumstances from Ross Taylor. After winning the toss and batting in his first test as captain in Cape Town - without Taylor - New Zealand were dismissed for 45.
Afterwards, over a beer in his room alongside coach Mike Hesson, manager Mike Sandle and assistant coach Bob Carter, they came to a conclusion.
"The team had no 'soul'," McCullum said. "We were full of bluster and soft as putty. It was the first time I had stopped to consider this in 11 years of international cricket.
"As New Zealand cricketers we wanted to remove a lot of the analysis; we wanted to be 'blue collar' in how we went about things, not aloof and superior. We planned less and had fewer team meetings."
Watch: McCullum on respecting the opposition:
Watch:McCullum on retirement:
McCullum said Hughes' death in November 2014 while they played the third test against Pakistan in Sharjah, inadvertently enabled them to unshackle.
"My initial attitude was that we shouldn't be playing. I looked around the dressing room and felt that no one wanted to be playing cricket. It had lost all meaning."
The teams took the next day off. McCullum rang sports psychologist Gilbert Enoka.
"Gilbert was incredible. He said we should not judge anything that anyone did during the week and that people should grieve in their own way, and concentrate their energy and emotions on themselves rather than the team.
"He told me to try and bring everyone together; to try to lighten the mood if at all possible. Most meaningfully Gilbert said; 'All your preparation, all you have ever thought about in cricket, just throw it out the window for this one game.'
"The outcome of the 'uncaring', no consequence play was a revelation to me. I suspect it was something I had been trying to achieve on a personal level for years; but I had been unable to do so, except for fleeting moments.
"There was an instinctiveness that took over - no fear of failure."
McCullum made 202 and New Zealand won by an innings and 80 runs.
He eventually led his team to a New Zealand record of seven consecutive undefeated series, and an inaugural World Cup final.
McCullum has been invited to join the Marylebone Cricket Club's cricket committee from October 1.
And, as if he can't get enough of the Lord's venue, he is also playing for Middlesex in England's T20 Blast.