A woman who bludgeoned her husband to death with a hammer is set to challenge her murder conviction in what is being described as a landmark case.

Sally Challen, 65, whose real name is Georgina, admitted killing 61-year-old Richard in August 2010 but denied murder.

Her lawyers argue she was driven to kill him after enduring 40 years of psychological abuse at his hands.

Her case will be heard at the Court of Appeal in London on Wednesday.

Challen, from Claygate in Surrey, argues she was a victim of "coercive control" due to her husband's behaviour.

Justice for Women, which has been campaigning to overturn the conviction, said he "bullied and belittled" her and "controlled their money and who she was friends with, not allowing her to socialise without him".

In a statement, Challen's son David and his brother James said: "Our mother's appeal is a landmark case, the first of its kind to use coercive control as a part of a defence to murder.

"This appeal crucially provides an opportunity to recognise the lifelong abuse Sally suffered and, in the hope of understanding the cause of her actions, provides an understanding of how she was driven to take the life of our father, Richard."

Challen was jailed for life in June 2011, and ordered to serve a minimum of 22 years, but later had the jail term reduced by four years on appeal.

She had denied murder, claiming diminished responsibility.

The defence of coercive control was only criminalised in 2015, four years after the trial.

Challen's lawyers will argue that if it had been available at the time she would not have been found guilty of murder.

Form of provocation

They will ask the court to overturn the murder conviction and substitute a manslaughter conviction in its place.

Challen's solicitor and co-founder of Justice for Women Harriet Wistrich said: "We are not arguing in this case that coercive control would provide a complete defence to murder, but the circumstances of a lifelong marriage amount to a form of provocation, which should reduce a murder conviction to manslaughter."

The appeal is expected to last two days.