In 2000 the Law Lords introduced the defence of provocation. This meant that battered women who kill their violent partners could rely on this defence if they acted through fear or despair. A successful defence of provocation reduces a murder charge to manslaughter.
At the time this was hailed by women's groups as a breakthrough. But is it back firing with husbands saying they were 'provoked' into killing their 'unfaithful' wives.
Jenni talks to Harriet Wistrich, a solicitor who has worked with Justice for Women and Simon James, a criminal barrister who has worked on a number of provocation cases.