THE mother of a former York schoolgirl who was bludgeoned to death with a claw hammer by her husband has launched a campaign to keep him behind bars - with support from Carrie Johnson.

Joanna Simpson, originally from Badger Hill and the daughter of a well-known York builder and property developer, Christopher Simpson, was killed by her estranged husband David Brown in 2010, with their two children within earshot.

The British Airways captain was acquitted of murder but admitted manslaughter on the grounds of diminished responsibility and given a 26 year sentence, and he is due to be freed from prison on licence later this year.

Joanna's mother, Diana Parkes, has begun a campaign aimed at urging Justice Secretary Dominic Raab to intervene to block Brown's automatic release.

She warned that Brown will be "very bitter" when he enters the community, having lost his job, his high earnings and his children, who she says never want to see him again.

York Press: Robert Brown, who bludgeoned his wife Joanna Simpson to death and is now due to be released from prison later this yearRobert Brown, who bludgeoned his wife Joanna Simpson to death and is now due to be released from prison later this year (Image: The Press)

She said: "Most of his life before prison has been stripped away and he won't be able to contain his anger and will seek revenge."

The 83-year-old grandmother described the killing as a "life-changing tragedy which has altered my whole family's life forever, leaving my grandchildren, aged nine and 10, without a loving and caring mother".

Carrie Johnson, accompanied by her husband, former prime minister Boris Johnson,  recalled her fear over black cab rapist John Worboys' planned release from jail as she spoke in support of the campaign.

She spoke of her ordeal at the hands of Worboys after he was jailed indefinitely in 2009, with a minimum terms of eight years, and gave evidence against him at his trial.

She said: "I remember Hetti (Barkworth-Nanton, Ms Simpson's close friend) and Diana describing themselves as sitting ducks, powerless to do anything, and I knew that feeling from my own experience.

"When I found out the taxi cab rapist John Worboys was due to be released much earlier than we thought, with no explanation as to why, I remember feeling really scared."

York Press: Diana Parkes (right) pictured with the now Queen Consort and interviewer Emma Barnett when they appeared on BBC Radio 4's Woman’s Hour / BBC BreakfastDiana Parkes (right) pictured with the now Queen Consort and interviewer Emma Barnett when they appeared on BBC Radio 4's Woman’s Hour / BBC Breakfast (Image: The Press)

Speakers at the event included shadow domestic violence minister Jess Phillips, who said it was "unfathomable" that Brown, with his history of domestic violence, would be let out of prison.

The Queen Consort is among others who have supported Mrs Parkes' wider campaign to tackle violence against women, previously citing her as the inspiration behind her work with domestic abuse victims.

Camilla called last year for more action to address violence against women when she appeared alongside Ms Parkes at Clarence House for Woman's Hour and BBC Breakfast.

The Justice for Joanna campaign urges supporters to write to their local MP asking them "to put pressure on (Justice Secretary) Dominic Raab to take this case seriously and do the right thing - for Jo, for her family, for all women and girls".

Mr Raab has invited Mrs Parkes to meet with him next week to discuss the case, which he says he will be reviewing carefully.