Key Points:

Miriam Cameron will never forget the day 36 years ago when she met the dashing young Tim Shadbolt. The charismatic student radical spotted Cameron through a swarm of street performers and made a beeline for her.

Within a year, the idealistic young couple were celebrating the arrival of their first child, Reuben. "To Tim and Miriam Shadbolt," the birth notice read, "a young revolutionary son, 8 1/2lb - our thanks to the welfare state and those who man her."

Two months later, Miriam Cameron was back in hospital - but this time there was no cause for celebration. She was being treated for two black eyes after she says she was thumped by Shadbolt while she was breastfeeding her son.

For three decades Cameron has remained silent about her 20-year relationship with the Kiwi icon and Mayor of Invercargill - a man she says has traded on his image as a loveable buffoon and peace-loving activist. In reality, she says, Shadbolt was also a wife-beater, a serial adulterer and a chauvinistic father who put the pursuit of political power and public office above his family.

Reuben, she says, suffered more than anyone.

Ten days ago Reuben was served with a trespass notice ordering him to stay off Cameron's North Shore property. This followed a series of abusive outbursts towards his mother.

Cameron insists it was an exercise in tough love, saying her son's recent erratic behaviour is a consequence of the feelings he harbours towards his father.

The 56-year-old Auckland artist now believes it is time the record was set straight - time Shadbolt faced up to the hurt he caused her and her children. Thirty years, she says, is long enough to live with a dark secret.

Cameron says that while she forgives Shadbolt, she can never forget.

The worse of the two beatings she suffered, she says, was in 1989, when he was Mayor of Waitemata City. Shadbolt, she says, punched her in the face at least five times after she accused him of being a compulsive liar. She recalls being treated at North Shore accident and emergency for two black eyes and gashes to her face.

"As he punched me, he kept saying 'You're just going to have to learn, you're just going to have to learn'. I saw stars. It was a vicious attack."

Shadbolt, she recalls, turned up on the doorstep the next morning and could barely believe his eyes. "Oh Mims, I didn't do that, did I?" she remembers him saying.

Cameron insists, though, there is a nice side to the colourful Mayor of Invercargill and that after the 1989 beating he was genuinely remorseful.

However, despite his remorse, she says, it wasn't the first time Shadbolt had let fly with his fists. In 1971, shortly after Reuben was born, Shadbolt backhanded her with a closed fist after she admitted to a one-night stand with a man she admitted to "fancying for a long time". She said she wanted to teach Shadbolt a lesson because of his own infidelity.

"We're in the car on Mt Eden Rd, and I'm breastfeeding the baby when I break the news to him. This fist comes flying, and before I knew it, I was seeing stars. I couldn't fight back because I had Reuben. I had two black eyes and a big nose for about a week. I looked horrible.

"I told him, 'Right, Tim, you're going to take me to Auckland Hospital, and you're going to face up to this.

"We walked in there [the hospital], and I remember telling the nurse on duty that 'My man here has just hit me and I think my nose is broken'. She looked at Tim and said, 'That's not very good, is it'. Tim was looking very sheepish.

"The nurse asked me if I wanted to lay charges, but I said no. We were political activists, so we viewed the police as our enemy."

Shadbolt declined the opportunity for an interview with the Herald on Sunday but in a statement said: "Miriam and I have had a close working relationship for 37 years. Only three months ago we completed a very successful property development in Queenstown. Miriam has often spoken out publicly on intimate details regarding our relationship. On all of these occasions I have declined to comment on specific allegations, and that remains my present policy."

Cameron met Shadbolt in 1970. He was tall, dark and handsome in a quirky sort of way - and never short of female company.

In those days, Shadbolt was a cult figure in student circles. Never shy about backing his words with actions, Shadbolt rebelled against anything that represented the establishment: the war in Vietnam, apartheid, local and central government.

The 23-year-old made an instant impression on the 19-year-old feminist. "He came up to me. Of course, we all knew who he was," Cameron said.

"I was in love with someone else at the time, but I suppose it was fate. I didn't like the way people hung around him like sycophants, but I remember him giving me the eye. I think I liked his honesty. He basically came up to me and said, 'I want you', and being a bit of an anarchist myself, I admired that. And that was it. That was the beginning of it all."

Within a week of meeting Cameron, Shadbolt asked her if she would move in with him. Shadbolt had already been married and was a father, a situation which he would later describe as a "monstrous trap". In his book Bullshit and Jellybeans he wrote: "I just couldn't face the situation. My friends were saying things like 'I hear you're married Tim - never mind, you've had a good run. It happens to all of us sooner or later'.

"The marriage label was like death. I fled into the student ghettos of Grafton, moving from flat to flat, leaving half-signed mortgage papers, flustered salesmen and screaming mothers behind."

Cameron had her sights set on being a painter and wasn't sure whether Shadbolt was husband material.

"But he must have got to me, because it wasn't long after that I got pregnant," she said.

On October 7, 1971, Reuben Shadbolt was born, but cracks were already starting to appear in the relationship. Cameron suspected Shadbolt was being unfaithful, so she packed her bags and left him. But, she says, she loved him and couldn't stay away for long. Three weeks later, he turned up at her home.

"He did this performance, and after half an hour I was feeling sorry for him. He was lying on the floor crying. He really did a number on me."

Cameron says she returned home, but she believed the womanising was still continuing and thought it was time to teach Shadbolt a lesson and show him how it felt to be betrayed. "It was the only way to show him what it felt like," she says.

She recalls catching up with a long-time friend at a local hotel and then spending the night with him. "I could now go home and tell Tim I was part of this open relationship that was so important to him."

Shadbolt, she says, was furious when confronted with the news and hit her in the face.

In later years, Shadbolt would admit it was tough turning his back on women who came on strong. Describing himself as a "bit of a rock 'n' roll star in the political sense", he believed most men would react the way he did if put under the same pressure. "I feel really lucky, privileged and honoured when women show interest in me, and I can't bloody understand it myself."

Cameron says the incident on Mt Eden Rd was a wake-up call for Shadbolt, and for the next five years he remained faithful (at least as far as she knew).

But as a father, Cameron says, he still left a lot to be desired. "I don't think he ever really loved Reuben. I honestly think he was jealous of him. That is why Reuben is now so damaged, emotionally. At the time, I suppose, I had this feminine arrogance about the situation. I thought so long as I loved my son, it didn't matter that the father was a bit cold."

Shadbolt's disregard for his son was there, she says, for friends to see on their return from a three-week trip with other young socialists to China. They held a slide evening at home, and at supper time Reuben was passing out sausage rolls to the guests.

"Tim had hurt his toe on a concrete job that day, and little Reuben accidentally stood on his foot while handing out the sausage rolls. Tim went whack with his hand right across his face. The whole room was stunned.

"Reuben was crying. I remember seeing this hurt on the poor kid's face. I wanted to throttle Tim."

Reuben told the Herald on Sunday he recalled the incident and how numb his face felt at the time. "I do remember my father hitting me and just feeling absolute hate towards him for half an hour, and my face being all numb and aching."

In an earlier statement to the Herald on Sunday last week, Tim Shadbolt said: "I have three sons and I love them equally, but Reuben is the one I worry about.

"It is incredibly distressing when a family member is abusive. I have tried my best to encourage him to get help, but he is 35 years old now, so there is very little I can do. I have always been very accessible to the media, and I guess your interest is natural, but this is a private matter. I love my son and want to protect his privacy."

In 1976, Cameron and Shadbolt married, despite her nagging doubts about his suitability as a husband and father. Shortly after, she became pregnant with second son Benjamin.

A few years earlier, she had had an abortion - "I just couldn't cope with having another child with someone like Tim" - but agreed this time to go through with the pregnancy, thinking another child might improve things in the relationship.

But things didn't improve, they got steadily worse. One incident, she says, sticks in her mind.

Shadbolt, she says, had picked up some hitchhikers, and with not enough room in the car for everyone told his dog Brutus to get out of the vehicle. They never saw the 8-year-old german shepherd again.

There was also suspicion of further infidelity but nothing Cameron could prove.

The next few years passed without incident, and in 1983 Shadbolt decided it was time to ditch the concrete mixer for politics.

After years of relative obscurity, he made a bid for the Waitemata mayoralty - and against all predictions won.

The former student radical had come full circle. He even had designs on becoming prime minister.

But, Cameron says, Shadbolt the lofty idealist quickly became Shadbolt the sellout. He refused to ditch the mayoral robes, the council Daimler or the other trappings of power. Years later he infamously lost the mayoral chains at a party.

"Fame was a poison. Everywhere he went people adored him, so he was living in the alter-ego."

Shadbolt stood for re-election in 1986, but this time around he took a team in with him - Tim's Team. They swept the election.

Shadbolt had big ideas. One was a far-fetched plan to build a dome in Waitemata City. It was typical Shadbolt, says Cameron.

Shadbolt, she says, was also drinking heavily. "Everywhere he went people offered him booze. But I don't blame him for that. It was a stressful job. He needed a drink."

By the beginning of 1986, Cameron says, she had had enough. She had become suicidal and again had suspicions that Shadbolt was being unfaithful. She confronted him and says he confessed to a handful of one-night stands. She thinks it was only the half of it.

"You know it when your partner is playing around on you. He was sleeping with sycophants up and down the country. I was absolutely devastated to hear the truth.

"I can forgive him for sexual disloyalty, but what I can't forgive him for is the damage that it has done to my children.

"That is why I felt suicidal. I was asking myself how I could be hoodwinked by such an ego-junkie.

"When you finally realise it [the relationship] has all been a lie literally, it does tamper with your sense of sanity. You start to think, what was real all these years? Who am I, who is this guy? I was a mess and my kids had to see this."

The couple separated but reconciled shortly after in the hope of saving their marriage. "I wasn't strong enough to say it's all over."

The final straw, she says, came in 1989 following what she claims was a violent incident in the mayoral vehicle. "I was a broken person by then, trying to hold something together."

Cameron says they had been driving from West Auckland to the North Shore to pick up Reuben when she confronted Shadbolt over who he had loaned the mayoral car to.

"He was ducking and diving. I told him, 'That's it, pull over, let me out'. I had lost it.

"We get over to the Shore, he pulls over, and he pulls my hair back, and he just pulverised my face.

"As he punched me, he kept saying 'You're just going to have to learn, you're just going to have to learn'. I saw stars. It was a vicious attack."

Cameron says she then went looking for help. She recalls spotting a light on in a house up the road and going to the door, but there was no answer.

"It is a freezing winter night. I was feeling dizzy and I needed to find help. It was a nightmare. I was worried about how I was going to protect my children from this.

"I pushed this door open and there was a couple sleeping soundly, and their children were snoring in the next room. I thought, 'I can't do this to them'. So I walked quietly back out and closed the door and walked up the road further."

Cameron says she then spotted another light on in a house further up the road. "I must have had an angel looking after me. A trainee doctor answered and then, when I saw the look on his face, I knew how bad I must have looked. I looked at this face [in the mirror], it wasn't me. It was horrendous."

She says he took her to the North Shore accident and emergency clinic where she was treated and stitched up. Her immediate fear was facing her children in the morning - and that the story would end up the newspapers.

"The story I told my kids was that I had got the bash by white trash. I'll never forget looking into the faces of my children. They knew I was lying, and I had never lied to them before."

Shadbolt turned up on the doorstep the next morning, she recalled, and could barely believe his eyes.

Reuben Shadbolt also recalls seeing his mother after the incident - and says he was so angry about it, he attacked his father in the living room of their house. He says he tried to knee Shadbolt in the ribs but was only a "skinny little teenager" so made little impression.

"I knew what had happened. My brother might not have been old enough to know, but I could tell by my father's body language what had happened." Benjamin Shadbolt declined Herald on Sunday requests for an interview.

A month later, Cameron left Shadbolt for good. That year Shadbolt lost the mayoralty. Three years later they divorced.

In 1993, Shadbolt picked up the pieces, becoming Mayor of Invercargill, and in 2005 appeared in Dancing with the Stars and scored a cameo role in The World's Fastest Indian.

Family friend Pita Turei remembers Cameron and Shadbolt as a "dynamic couple" who attracted people who were "charged by their energy".

Cameron and Shadbolt are now both in long-term relationships and speak only occasionally.

"I just feel so sorry for both my kids. I have forgiven Tim, but I can't forgive him for what he has done to our children."

Reuben says while he doesn't hate Shadbolt, he does have a hatred towards him for his "inability to look at his own faults" - faults which have nearly driven him and his mother mad with anger and sadness.

The Shadbolt Story

* Timothy Richard Shadbolt, born February 19, 1947, in Remuera, Auckland. Shadbolt's father killed on a training flight in 1952.

* Shadbolt elected to School Council and made a prefect. In 1966 attends Auckland University, elected to student executive, becomes editor of Craccum.

* Shadbolt prominent in radical Progressive Youth Movement. Arrested 33 times in political protests.

* Leaves university in 1970, meets Miriam Cameron. They form a commune and concrete cooperative at Huia. 1971, first son, Reuben, born. Shadbolt and Cameron marry in 1976. Second son, Benjamin, born a year later.

* 1983: elected Mayor of Waitemata City. Re-elected 1986, but loses the following election in the newly-formed Waitakere City. During his reign, he famously lost the mayoral chains.

* 1993: becomes Invercargill's mayor. Celebrates, towing his concrete mixer behind mayoral car.

* 1994: contests Selwyn by-election for NZ First but loses. Then loses council election but remains on the body. He is re-elected Invercargill mayor in 1998, a position he has held since.

* In 2005, New Zealand Toastmasters award Shadbolt the Communicator of the Year award.

* Shadbolt has a cameo role in movie The World's Fastest Indian and competes in Dancing with the Stars.