Days after his mum’s murder by her twisted ex, 15-year-old Bengi Stubbings crept up to the crime scene – once his home – and stole a photo of her left by a mourner.

“I realised I didn’t have one,” he says quietly. “I kept ringing her mobile every day. I didn’t think it was real.”

Six years on, Maria Stubbings’ mobile no longer rings, and Bengi, 21, is beginning to grasp the truth of her death.

In December 2008 she was strangled with a dog lead by ex Marc Chivers, 47, who dragged her body to the downstairs toilet of the home she shared with Bengi.

Chivers then continued living in the house, telling Bengi that Maria, 50, was visiting a friend, and the toilet was blocked.

For three days Bengi went to and from the house, even spending a night there with her killer, before police finally found her body hidden there.

Marc Chivers
Murderer: Chivers had long history of violence

But now Bengi and his family have a new, shocking, reality to face – the revelation police failings led to his mum’s death at the hands of a man who, unbeknown to her, had already killed.

The failings emerged at an inquest that closed on Tuesday. It was launched after a campaign by her family, who also won a civil claim against the force.

Bengi says: “Maria’s murder is as much the fault of Essex Police as the murderer himself.

“We fought in honour of Maria and in the hope things will change to protect others.”

Chivers had already served three months for assaulting Maria five months before her death.

Until he was jailed, she had no idea he had spent 15 years behind bars for strangling an ex in Germany.

After the attack on Maria, she had a panic button installed, but it was ­disabled when Chivers was jailed and was never reconnected when he got out.

Promised police visits were also not made, despite Maria complaining of Chivers breaking in, the inquest heard.

And when officers finally showed up at her door in Chelmsford – too late, with her body just feet away – they were greeted by Chivers, accepted his story she was away and left a calling card.

Bengi, his half-sister Celia and Maria’s brother, Manuel, are reeling over the revelations.

Maria Stubbings' brother, daughter and son
Reeling: Manuel, Celia and Bengi with a picture of Maria

Bengi says: “When she called for help, they found every excuse to do nothing. Words fail us. Maria paid the price for the failings with her life.”

Maria met Chivers in March 2008, walking her dog. She fell for him – with no idea he had only been out of jail two months.

He began attacking her but Maria kept it from her family.

That July, Chivers hit Maria and cut off her underwear. He was then charged with assault and jailed.

Yet Maria still did not tell her family what he had done. Bengi says: “I wish I’d been able to help.”

Soon after his release, Chivers contacted Bengi, who still did not know about the violence.

And on December 11 Chivers let himself into Maria’s home. She walked in to find him there. Her call to the police was played at the inquest.

She was promised a visit that day, but no one went. Bengi says: “It was difficult to hear her asking for help like that.” The last time he saw his mum was December 16, 2008.

He spent the night at his dad’s and when he got home the next day Chivers let him in.

Maria Stubbings' house in Great Baddow
House of horrors: Family home where Maria was killed

Bengi, who had pals over, admits: “I just thought it was nice Mum had gone to her friend’s. He was hanging out with us, watching films, taking us out in Mum’s car.”

Finally, on the 19th, the police found Maria’s body and arrested Chivers. But the family say they first heard the grim details in a paper on Christmas Eve.

Student Bengi says: “We knew she’d been murdered but not that she had been strangled with a dog lead and dumped in the downstairs toilet. It feels like another layer of betrayal.”

Chivers was jailed for life. Police were criticised for incompetence, inadequate training and failure to arrest him a number of times.

Maria Stubbings with son Bengi
Bond: Maria with a young Bengi

Chief Constable Stephen Kavanagh apologised to the family. He said: “The way we deal with domestic abuse has changed greatly.

“We failed in our duty to protect Maria, and her son. I am determined to make sure we never fail a victim again in the same way.”

  • The family, with charity Refuge, are petitioning for a public inquiry into the way domestic abuse victims are treated by police and other agencies. Sign at www.refuge.org.uk/publicinquiry .