A formal review will be held into how the case of Killamarsh criminal Damien Bendall was handled by probation officers before he murdered three children and his pregnant partner, the Ministry of Justice (MoJ) has said.

Deputy Prime Minister Dominic Raab asked the Chief Inspector of Probation to investigate Bendall’s court files after the ex-con was sentenced to a whole-life order for the murders on Wednesday.

Bendall, 32 and from Park South, was already in the probation system for arson, robbery, attempted robbery and grievous bodily harm convictions.

He had been serving a 17 month prison sentence, suspended for 24 months, for arson when he carried out the killings.

According to the Daily Telegraph, the probation officer who assessed his record for his sentencing at Swindon Crown Court in the arson case has since been sacked.

The probation officer was found guilty of gross misconduct after erroneously categorising Bendall as “medium risk” rather than “high risk”, according to the newspaper.

A second probation officer has also separately been found guilty of misconduct for later allocating Bendall’s case to a trainee.

The BBC reported that one of the conditions of his suspended sentence was an overnight curfew at his partner Terri Harris's home in Chandos Crescent.

Bendall had also been jailed for a botched knifepoint robbery at a convenience store in Nythe, Swindon in 2015.

In September 2021, Bendall used a claw hammer to murder 35-year-old Terri Harris, her 11-year-old daughter Lacey Bennett, her son John Paul Bennett, 13, and Lacey’s friend Connie Gent, 11.

Bendall also admitted raping Lacey during the attack, which took place at the home he shared with Ms Harris in Killamarsh, Derbyshire.

A spokesperson for the MoJ said: “These were appalling crimes and our thoughts remain with the victims’ families.

“The Deputy Prime Minister asked the Chief Inspector of Probation to conduct a review of this case and we will respond further once this is published.”

Former justice secretary and South Swindon MP, Sir Robert Buckland, who left the cabinet role just three days before the Killamarsh killings, described the miscategorisation of Bendall as a lower-risk offender as “an appalling failure”.

He said: “I think we have to acknowledge that such an error is just an appalling failure.

“The ministry has to be as open and transparent as possible about why it happened, and most importantly to make sure the risk of that happening again is kept to a minimum, if not eliminated.

“Frankly, there should be processes in place that means various thresholds and tests would be met before that sort of fundamental mistake could be made.”

The Chief Inspector of Probation’s review is likely to be released in the new year.