The government has launched its new Domestic Violence, Crime and Victims Bill.

Announced in the Queen's Speech last week, the bill aims to establish a new independent Commissioner for Victims and Witnesses, which will police a new code of practice to extend across the criminal justice system.

The police will be granted new powers to deal with cases of domestic violence.

Restraining orders may be granted against people even if there is insufficient evidence to convict them of violence towards their partner, under the measures contained in the bill.

Key local agencies will be required to investigate when a partner dies in a domestic violence situation - 120 women and 30 men die each year at the hands of their current or ex-partners.

The new legislation will also extend police powers towards same sex and unmarried couples who have never cohabited.

"Domestic violence is an abhorrent crime, which costs the lives of two women every week, and accounts for almost a quarter of all violent crime," said home secretary David Blunkett.

"This largely hidden, much under-reported crime tears apart the lives of far too many families, terrorising and brutalising them in their own home - the very place they should feel safe.

"The government is determined to tackle domestic violence, and bringing forward the biggest reform of the law in this area in 30 years.

"I intend to make sure that victims get the help, support and protection they need, and to make sure that the police and the courts have the powers they need to convict and punish these offenders."

The move has also been welcomed by constitutional affairs secretary Lord Falconer.

"These proposals confirm the government's commitment to putting victims at the heart of the criminal justice system," he said.

"Victims of domestic violence should be confident that the courts will put their needs first and have the powers to give swift and effective protection.

"The measures contained in this bill will do just that, making it easier for victims to seek and get help from abusive, violent partners."

Solicitor general Harriet Harman spoke at a Women's Aid conference where she set out the government's agenda on the issue.

"The stay away order will...be issued in the magistrates and crown courts where there is a conviction for domestic violence, but also crucially where there has been an acquittal," she said.

"Courts will be able, even as they are acquitting the defendant, to ensure the victim's safety by ordering him to 'stay away'.

"It will be, if you like, a yellow card and he will know that if he breaches the order that in itself will be a criminal offence punishable by up to five years in prison."

"We often talk in government about the importance of diverting offenders - particularly young offenders - out of the criminal justice system earlier," she added.

"In this case we want more offenders diverted into the criminal justice system at an early stage.

"Because then we can ensure that their behaviour is addressed and they receive the appropriate punishment for their crime."

Speaking at his monthly press conference the prime minister gave his personal backing to the bill.

"It will ensure at last that the law properly reflects modern society's view that domestic violence is not something to be played down just because it happens behind closed doors or in the home," Tony Blair said.

But the home secretary and the solicitor general are said to be at odds over whether a "provocation" defence should be abolished in murder cases involving domestic violence.

Shadow minister for women Caroline Spelman welcomed the legislation but argued that more needs to be done to enforce existing laws.

"Bringing forward a bill is not a panacea in changing the culture of domestic violence. Currently, domestic violence is not legal but is acceptable. The government must raise awareness that it is both illegal and unacceptable," she said.

"There is a split in the government, with the home secretary and the solicitor general said to be at odds over whether a 'provocation' defence should be abolished in murder cases involving domestic violence. This should have been resolved before the bill came to this stage.

"Over 60 per cent of sentences are increased as a result of appeal, this indicates that the judiciary is poorly educated when it come to sentencing crimes of domestic violence and that sentencing is systematically too light."

"More and more refuges are running on a shoestring, currently there is only one bed available per 200,000 of population," she added.

"Existing harassment laws provide injunctions but fewer and fewer solicitors are willing to do injunctions work as legal aid."

Liberal Democrats described the bill as "welcome but long overdue".

"Each week two women die as a result of domestic violence and many cases go unreported through fear and intimidation," said home affairs spokesman Mark Oaten.

"Tackling domestic violence and providing better witness protection is vital, but the government must also look at how children involved in domestic violence are subsequently protected."