The parents of notorious serial killer Joanna Dennehy, formerly of Harpenden, have spoken on TV about how their daughter’s heinous crimes have shattered their family’s lives.

Herts Advertiser: Joanna DennehyJoanna Dennehy (Image: Archant)

Over the course of 14 days in 2013, she murdered three men in cold blood and left another two fighting for their lives.

In an interview being aired this weekend in an episode of Crimes That Shook Britain her mum, Kate Dennehy, says “the girl that killed those people is not my daughter, my daughter’s that nice 14 year old that never came home.”

Dennehy is one of only three women in the UK to be handed a whole life sentence, with no hope of release.

In February 2014, she was given an all-life sentence for the murder of three men, and stabbing of two more.

Herts Advertiser: Dennehy sticking her tongue out as she brandishes a jagged knife with handcuffs attached to her trousers.Dennehy sticking her tongue out as she brandishes a jagged knife with handcuffs attached to her trousers. (Image: Archant)

She admitted the murders of Lukasz Slaboszewski, 31, Kevin Lee, 48, and John Chapman, 56, in and around Peterborough in a 10-day period in March 2013.

She also pleaded guilty to two counts of attempted murder and preventing the lawful and decent burial of her murder victims.

During this Sunday’s Crimes That Shook Britain episode, Kate Dennehy says that when Joanna, who was born and raised in Harpenden, was young she used to enjoy going to the playground and was a “happy, very sensitive girl”.

She adds: “If she stood on a worm or something she would be really upset; if it had died she used to take them to bed with her, so she was a loving girl.”

However, during her teenage years, her parents noticed a ‘dramatic change’ in her personality, when she started to play truant from school, and was often in trouble with the police.

Her dad, Kevin Dennehy, says that he assumed she was merely going through an unruly stage - including starting a long term relationship with a man six years her elder - but would “come back [home] at 18, 20 healthy and okay”.

Kate says: “But she never did come back to us.”

She became estranged from her parents, and her life spiralled into one of crime.

When Dennehy was taken into police custody, 60 miles from Harpenden, her parents were informed of their daughter’s whereabouts for the first time in a decade.

Kevin said he and Kate were ‘devastated’ to hear about the serious crimes she had been charged with.

Dennehy would later be recognised as a pathological liar with psychopathic tendencies.

Kate says: “When I saw CCTV footage of Jo it was like somebody I didn’t know. She’s standing there being charged, smiling and laughing with police officers – that’s not the kind, loving Joanna that was our baby.

“When I heard [later] that Joanna had pleaded guilty I was very surprised, because I thought that she wanted notoriety. She wanted to be in the limelight. She wanted to be recognised as doing something.”

Speaking about her daughter’s subsequent imprisonment, Kate admits: “If I’m brutally honest, I don’t ever want her to come out, I think because she would do it again, because she has no remorse. She deserved what she got. The world’s safer without Joanna in it.”

But her cold-blooded crimes have shattered the lives of her own family, with the serial killer’s dad saying: “We have not talked to her, spoke to her; I don’t think that she wanted to speak to us anyway, and I wouldn’t like to see her.”

Kate adds: “To me, she doesn’t exist any more because she’s destroyed people, so I would never want anything to do with her, because she’s not my Jo.

“The girl that killed those people is not my daughter – my daughter’s that nice 14 year old that never came home.”

• Crimes That Shook Britain continues at 9pm on Sunday, January 22, exclusively on CI.