Harriet Harman: The QC who has learnt to keep her own counsel may yet earn a return to Cabinet

Harriet Harman's ministerial red box lies open on her desk. Her conversation is peppered with references to Tony. The message is clear – the Member of Parliament for Camberwell and Peckham is back at the heart of Government and proud of it.

Eighteen months ago, Ms Harman, one of New Labour's best-known faces, was languishing on the back benches, having been dropped from the Cabinet in Tony Blair's first reshuffle afterthe landslide election of 1997.

Many suspected that New Labour's Secretary of State for Social Security had paid the ultimate price for not believing in some of the policies she had been asked to enforce.

Ms Harman's Radio 4 interview with John Humphrys over cuts to lone-parent benefits, in which she demonstrated an inability, or unwillingness, to mount a cogent defence, was held up as evidence of her disloyalty. So was her decision to send her eldest son to a distant grammar school instead of the local comprehensive.

Throughout her exile on the back benches, she took her medicine without protest while at the same time skilfully distancing herself from any old Labour plots to embarrass their New Labour masters.

Last year, Ms Harman's loyalty was rewarded when she was appointed Solicitor General, the first woman to attain such a rank.

Since then, her profile has remained low key, leading many to suspect that in return for an early return to the Government she has promised to keep her counsel. Does Ms Harman think she has been silenced?

"Absolutely not," she says. "I think the law officer's role is a very important role. It's not just a place to be quiet in Government. I did actually say that if I was to be returned to Government I should be given a job to do with the law, which would have either been in the Lord Chancellor's Department or here [Law Officers' Department]. I think it's just the way things fell.

"I would have been more than happy to have found myself in the Lord Chancellor's Department. I don't believe the fact it is a behind-the-scenes role has anything to do with me having being given it. Nor do I think there was any intention of having me in Government but behind the scenes."

The very different demands and unique constitutional position of the Solicitor General mean that Ms Harman has spent her first year learning the ropes of her job. As one of the Government's most senior law officers, the Solicitor General devotes much of her time to providing confidential advice to ministers – not the sort of work that lends itself to press releases or lobby gossip.

Ms Harman is acutely aware of the need to respect the sensitivities of her post. "I have wanted to make clear to everyone I deal with, the Bar, the judiciary and other departments, that this is not just an unbroken line of me being in Government – this is a very big break and a very different role."

The unforgiving restraints that go with Ms Harman's second job in government were tested to the full during the Damilola Taylor case. Although the boy's killing took place in the heart of her constituency, Ms Harman's opinions on what went wrong with the subsequent police investigation and prosecution have been conspicuous only by their absence. As one of the law officers responsible for the Crown Prosecution Service, the agency at the centre of criticism after the case, she could not make her feelings public.

Nevertheless, Harriet Harman QC has found some time, and leeway, to work on the kind of political issues for which she has built her career. At the top of her agenda is the need to tackle domestic violence.

She says 25 per cent of violent crime and a third of homicides have a domestic context. "The Government can't live up to its commitment to tackle violent crime unless it tackles domestic violence."

The time has come, she says, for a change in public attitude so people no longer turn a blind eye to wife beaters. "Once upon a time people thought it was not only all right for a husband to beat his wife it was also a man's duty," she says. "Then it was not legal to beat his wife but if he did, she must have brought it on herself. I can remember that attitude from my mother's generation. Now it's in its third phase – it's a bad thing but we probably can't do anything about it because it's behind closed doors and it's all too difficult."

Ms Harman is fighting to bring about a fourth phase. "Domestic violence is something that the criminal justice system can do something about and must do something about."

One way the Solicitor General, and her boss, the Attorney General, Lord Goldsmith QC, can help to bring about this change is by referring to the Court of Appeal sentences that they believe are unduly lenient and undermine the public confidence in the criminal justice system.

In recent months, the law officers have enjoyed mixed success. This summer the Court of Appeal increased sentences imposed on two men convicted of beating up their wives. One was a retired professor aged 66 who broke his wife's ribs, punctured a lung and put her in hospital for four days. The judge took account of the man's depression, partly a result of his wife's decision to leave him for another man, his public service and his exemplary career, and imposed a community rehabilitation order. The professor had to have psychotherapy and 60 days of domestic-violence training but he avoided jail.

When the case came before the judges in the Court of Appeal, they agreed with the law officers that the level of violence would have justified a prison sentence and he was given a six-month jail term. In another domestic violence case heard the same day, a two-year sentence was increased to three.

But the traffic has not been one way. This month, a plea by the Attorney General for longer prison sentences for husbands who kill their wives was rejected. The court declined to interfere in three cases where the offender killed his spouse or partner in a ruling that makes clear a judge must be free to consider all the mitigating and aggravating circumstances in a case of domestic manslaughter. The issue is expected to go the Sentencing Advisory Panel, which guides the Court of Appeal on length of sentences.

Ms Harman knows these are very difficult questions for the courts and the Crown Prosecution Service. In many cases, she says, even when the beaten wife or partner is in hospital she is still begging the Crown prosecutor to drop the case. "She knows she has got to get better to look after her children. The last thing she wants is to have the stress of giving evidence. The prosecutor then has to decide whether to witness-summons her or whether to drop the case. Where does the public interest lie when she wants to drop the case and the couple are at the back of the court holding hands in love?"

More is now being done by the Government to tackle domestic violence, including the establishment of a ministerial committee where all departments work together. New Crown Prosecution Service guidance means that prosecutors don't automatically drop the case when the police say that the complainant is retracting her testimony.

So why the sudden interest in this hidden crime? "I think that has come about because there are many more women MPs. In the last two out of three Prime Minister's Questions, women have asked Tony about domestic violence. When I was first elected if you raised domestic violence once it was regarded as irrelevant, if you raised it twice you were regarded as obsessed. The fact there are more women MPs changes the climate in which this issue is discussed."

It is easy to see how Ms Harman's legal and political career has provided her with a apprenticeship for the job of Solicitor General.

Before she came to government she was an active civil rights campaigner, busy taking ministers to court when she thought their decisions were wrong or unreasonable. In this way, the law officers, who represent the Government of the day in legal actions, and Ms Harman had more than a passing familiarity of each other's work.

In the early 1980s she was on the receiving end of a contempt of court action brought against her by the former attorney general Sir Michael Havers QC. Ms Harman represented a prisoner against the Home Office, which she claimed was in breach of the rules on solitary confinement. Documents were read out in court, which she later showed to a journalist who had been present at the hearing. The Government said that by disclosing the documents outside the courtroom she was in contempt and successfully prosecuted her.

But Ms Harman won the day when she took her case to the European Court of Human Rights in Strasbourg and successfully argued that the prosecution had breached her right to freedom of expression. In the field of public law, Harman v United Kingdom is still a well-known case that is cited in textbooks. But Harriet Harman has ambitions beyond legal textbooks and her reward for not causing any waves as the first female Solicitor General may yet include a place in Tony's next Cabinet.