Proposed reforms of laws governing murder have been prompted by concerns about the different treatment of men and women in domestic violence cases.
It could mean a new defence in cases of prolonged abuse, the abolition of the 17th century defence of provocation and a more precise definition of diminished responsibility.
Over the years, a number of high profile cases have put a spotlight on the law. Here are a few of them.
Kiranjit Ahluwalia was jailed in 1989 for killing her violent husband.
Ms Ahluwalia's story has been turned into a film
She had suffered 10 years of rape and abuse by her husband and after he threatened to burn her with a hot iron, Ms Ahluwalia threw petrol over her husband's duvet and set it alight while he was sleeping.
He died 10 days later of his injuries and Ms Ahluwalia was charged with murder and sentenced to life imprisonment.
A key reason for the failure of her plea of provocation, which would have reduced the crime to manslaughter, was the time that had elapsed between her husband's last attack on her and her retaliation.
Her case was taken up by the pressure group Southall Black Sisters and after a retrial she was convicted of manslaughter due to diminished responsibility, sentenced to the time served already and released in 1992.
Her appeal set a historic precedent - that women who kill as a result of severe domestic violence should not be treated as cold-blooded murderers.
Ms Ahluwalia's autobiography inspired the 2007 film Provoked, which starred Bollywood actress Aishwarya Rai and British actor Robbie Coltrane.
Sara Thornton was jailed for life in 1990 for the murder of her alcoholic husband Malcolm.
Ms Thornton pleaded guilty on the grounds of diminished responsibility
The police had been called to the home on numerous occasions when she was being assaulted and an Alcoholics Anonymous representative saw her violent husband punch her.
A neighbour said he had witnessed her husband "beat her black and blue" and she was admitted to hospital unconscious.
According to pressure group Justice for Women, he had threatened to kill his wife and her daughter in their sleep. Fearing for their life, she stabbed him once and called an ambulance.
She pleaded guilty on grounds of diminished responsibility and was found guilty of murder. In this case, the judge said she could have walked out or gone upstairs.
In English law there is currently only one full defence to murder - self defence. Two other partial defences - provocation and diminished responsibility - reduce the charge from murder to manslaughter.
In order to plead provocation you have to show that you killed following a sudden loss of self control.
In 1996, Ms Thornton's murder conviction was changed to manslaughter and she was granted freedom.
In 1985 Emma Humphreys, aged 17, was jailed for the murder of her violent boyfriend Trevor Armitage.
Ms Humphreys served 10 years in jail
A former prostitute, Ms Humphreys had a troubled upbringing and had suffered months of severe physical, sexual and emotional abuse at the hands of her pimp Mr Armitage.
She stabbed him when she thought he was about to attack her again - but did not tell the murder trial about the abuse.
Ms Humphreys contacted Justice For Women in 1992 after seeing media coverage of the Sara Thornton and Kiranjit Ahluwalia campaigns.
In 1995, after a decade in prison, the Court of Appeal reduced her conviction to manslaughter and she walked free.
After her release, she was a campaigner for Justice for Women but died three years later after overdosing on a sleeping drug.
The organisation set up a memorial prize award in her memory.
In 1991, Joseph McGrail was tried for the murder of his wife.
He pleaded provocation on the basis that his wife was an alcoholic and swore at him. He killed her by repeatedly kicking her in the stomach while she was drunk.
The judge expressed his sympathy with Mr McGrail, saying: "This lady would have tried the patience of a saint".
He was given a two-year suspended sentence and walked free.
Les Humes stabbed his wife Madeleine 12 times in 15 minutes in front of her children after she confessed to an affair with her karate instructor.
In 1992, the court heard how their teenage daughter tried to seize the knife from Mr Humes as he repeatedly stabbed her mother.
Mr Humes, who said in court he "just saw this red mist", was jailed for seven years after the Crown Prosecution Service accepted an admission of manslaughter and dropped murder charges.