His story is not, however, unblemished.
In 2009, it was revealed that he had improperly claimed a housing allowance of $900 per week in respect of a house in Wellington that was owned by his family trust, and in which he and his family had lived for some time, while at the same time claiming that his principal residence was in Southland.
He duly repaid the $32,000 that he should not have received.
This revelation and his admission of wrongdoing did not, however, dissuade his colleagues from electing him a few years later to the party leadership.
The polls show that he continues to enjoy widespread support from the voters.
The second of the two protagonists of our story - let us call her Citizen B - is a younger Maori woman who has also enjoyed a successful political career.
She was elected as co-leader of her party and has commanded wide respect for the efforts she has made to draw attention to environmental and social issues that she thinks are important.
In a perhaps misguided attempt to highlight one such issue - the struggle for those dependent on benefits to provide (especially for families with young children) food on the table - she revealed that she had more than a decade ago (and as a solo mum) lied to the authorities so as to claim a larger benefit (larger by $50 per week) than she was entitled to.
This revelation created a storm of protest - from the media, sections of the public, fellow politicians and even from her own party colleagues, some of whom declared that - as a matter of principle - they could not represent their party while she remained as co-leader.
She eventually felt obliged, as her revelation (and the storm that followed it) seemed to have provoked a sharp fall in her party's poll ratings, to resign as co-leader of her party.
Her transgression - and her decision to confess to it - may well have put an end to her political career.
The two protagonists have, in other words, both broken the rules and behaved in ways that risk forfeiting the trust and support of their fellow citizens.
But one has been made to pay a heavy price; the other has emerged unscathed and continues to enjoy public esteem.
Citizen A's error was committed when he was already in a position of responsibility, and earning a good salary; Citizen B, on the other hand, did so when she was yet to seek any public role.
Citizen A apparently enjoyed the financial support of a family trust, while Citizen B was a penniless solo mum.
Citizen A gained, by virtue of his failure to abide by the rules, a useful addition to his already substantial salary; Citizen B gained a much smaller sum which she applied to buying food for her child.
Citizen B confessed her mistake and was willing, for the sake of those she was trying to help, to endure the opprobrium that she knew would come her way, while Citizen A's error was disclosed only when official scrutiny revealed that he had broken the rules.
Citizen A continues to enjoy the prestige, esteem, salary and support from colleagues to which a Prime Minister is entitled.
Citizen B has, as the consequence of an unrelenting media campaign and her abandonment by her colleagues, been hounded out of her commitment to serving the public because she is apparently unfit to seek their support.
Charles Dickens himself could not have invented a more inventive and bizarre story line.
It is truly a tale of two citizens, and of how differently fate - and we - have treated them.
Why the difference?