In the eight years since her daughter Sarah was abducted and murdered by a paedophile, Sara Payne has become a familiar figure in British public life as the scourge of complacent politicians.

Now she is on the inside, and has given her first interview as the Government's Victims' Champion, flanked by no fewer than four officials from her new employer, the Ministry of Justice.

If this new role is, as some detractors have suggested, a canny move by the Government to neutralise one of its most articulate and vociferous challengers, it may have backfired. As her minders tapped into their BlackBerrys, Mrs Payne's voice filled the room.

She insists that she will walk away if she is not achieving what she wants.

“For me this is an extension of what I already do. If for one minute I thought this is what some people have portrayed it to be, I wouldn't be here,” she said. “Let's see if this is a promise that is real. If it is, then good. But let's not knock it down before it's started.”

She was, she said, surprised to get the job, beating five other candidates who were invited to interview by Jack Straw, the Justice Minister.

The details of what she will actually do are sketchy. She said that it was up to her to shape the role, which is intended as an interim measure before the appointment of a Victims' Commissioner a year from now. But she does know what she hopes to achieve. She said that she and her family were exceptionally well treated during that horrific summer of 2000, when Sarah was abducted.

“Everyone in our case went the extra mile. That is how things should be. And it's not always how it is.”

The police and members of the legal profession sometimes lost sight of what inspired them to take up their careers, she said. “They do it for the right reasons. But one of my jobs will be to remind people why they're doing what they're doing.”

She lives with her four children - including a daughter of 5 and a son in his early twenties - at her home in Surrey, and although she lives apart from her husband, they are still close. Her family is where she finds solace after she stopped being able to function - unable to shop or clean or stop herself drinking too much - in the years after Sarah's death.

They were also the ones who would keep reminding her about her true mission, she said, and take her to task if she became bogged down in bureaucracy. “Believe me, I have enough people around me - my family - that will quite happily tell me if I'm doing anything differently,” she said.

Had anyone close to her suggested that she was taking on too much? She has, she points out, changed 14 pieces of legislation and two laws, and continues to push for a Sarah's Law to give parents controlled information about where paedophiles live, as well as contributing to numerous other campaigns. Her work was recognised in the most recent New Year's Honours List, when she was appointed MBE.

Did she ever feel that she would like to stop and do something that did not involve crime or victims?

“No,” she said firmly. “If I could go back to where I was before, I would tomorrow. I would rather not have this voice or be in a position where I understand these things. But the point is, I am, and I have to use what I have to move forward.

“It has been tough, and I have tough times. Sometimes it would have been much easier to walk away. But it would be entirely wrong. I would have felt like I had let Sarah down, and myself down and my family down.”

So could it, in a sense, help with her grief, to work so hard for victims? No, she said, equally firmly. Respite does not come that easily. “Does this make any difference to my personal life? It doesn't bring me back Sarah, and that's the only thing that could make this better. But that cannot happen and nobody can give me that.”

Her mourning has since changed. “It's not something I wear here,” she said, banging the front of her jacket. “It's not an anger that is burning so brightly that I can't live and put one foot in front of another, but it is something that is always there.”

After Sarah's murder, Mrs Payne found herself shocked by the lax laws governing the release of offenders. “What I've discovered is that we've got some of the most apathetic people in the country in positions of authority,” she said at the time.

“I said those words eight years ago. Politicians have changed an awful lot. But they have to remember there are real people out there who are their bosses.”

When asked who had been the best Home Secretary, she smiled for the first time.

“The best are those that have strong convictions. Whether or not you agree with their core beliefs, you have to respect that. Rather than someone who changes their mind.”

A bit, perhaps, like Mrs Payne herself. She once called her motivation to campaign “selfish”, because it was a way of keeping Sarah's memory alive. Would she still describe it as selfish?

“Of course. I don't want her ever to be forgotten. I don't want any person who is murdered to be forgotten. I will do everything I can to make victims the forefront of people's minds.

“Let's look after those people. Because it's our job to, all of our jobs to, isn't it?”

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