The anguished letter written by the mother of John Banks' illegitimate son to the former Auckland mayor has been released by a judge.
The letter was written 18 years ago by Pamela Mayes, 27 years after she gave birth to Mr Bank's son Antony Shaw. In 2017, Mr Shaw successfully asked a judge to declare the former politician is his biological father.
Ms Mayes had a relationship with Mr Banks, which she says ended when she became pregnant and refused to terminate the pregnancy, despite pressure from him.
Ms Mayes said she raised Mr Shaw believing another man was his father but said she was prompted to come out with the truth after the birth of her grandson in 1997. Mr Banks had refused to engage and then declined to get a DNA test, she said.
In 1999, she wrote to Mr Banks saying she couldn't lie any more. The letter was filed as evidence in Mr Shaw's paternity case and is finally able to be reported.
The New Zealand Herald reported the contents of the letter on Monday.
"I've kept to your rules for 30 years - you wanted me to have an abortion and even gave me quinine from the Drug Co you worked at," Ms Mayes wrote to Mr Banks.
"When I wouldn't take that you told me to tell someone else it was their baby.
"As much as I didn't want to I did, then had to live with the lie and parent our son by myself for four-and-a-half years - in the days before income support," The New Zealand Herald reports.
At the same time Mr Banks refused to take responsibility for his child, he gave a passionate valedictory speech to Parliament, where he spoke of his heartbreak after growing up without a father.
"I am prepared to face up to the past and the lies and take responsibility for the wrongness that I did also," Ms Mayes wrote.
"You really did have control over me in those days. I should say I allowed you to control me but then I would have done anything you wanted me to do (except the abortion - I couldn't do that!)"
She went on: "There is a lot of pain and hurt still for the way I was treated and let down by you. I'm feeling really stressed and tearful now that it has all resurfaced again.
"I guess you can only keep things buried for so long."
Ms Mayes says the deception over her son's parentage had destroyed her relationships.
"I will have to live with that also," she wrote.
"But I have weighed things up and even if Antony doesn't want to know you or me after this it is important to me that the truth be told and you acknowledge him on his birth certificate.
"It seems to me that you want it all to go away - it won't.
"You said nothing would change and you would not make a fuss - would keep it private with our family - not even tell your adopted son except maybe when he was older.
"I feel that you have missed out on having a relationship with your son for nearly 30 years. (Your choice).
"Now you have a grandson and I think you will miss out on having a relationship with him."