A detective who lost his career after catching a double killer says he believes he could have found more victims if given the chance.
It is 10 years to the day since Sian O’Callaghan, 22, went missing while walking home from a nightclub.
The popular office worker had been partying in Swindon, Wiltshire before she set off on the 800m journey back to her flat.
But she never made it home, and her body was found five days later near Uffington, Oxfordshire.
Sian’s disappearance set in motion a series of events which ultimately led to the resignation of investigating officer Steve Fulcher.
The former detective superintendent was handed the 2011 case and clues led him to Christopher Halliwell, now 57.
The taxi driver was convicted of Sian’s murder in 2012 and handed life in prison.
But, during his arrest, Halliwell also told Fulcher about another killing he had carried out – and offered to show him the body.
His admission took police to the remains of Becky Godden, 20, who had disappeared from the same town in 2003.
Halliwell was sent down for her murder in 2016, where a judge described the killer as “both calculating and devious”.
But, between confession and conviction, Fulcher quit the police, after the High Court ruled his actions during the arrest were wrong.
It was decided that the detective had gone against standard guidelines (PACE) by failing to caution Halliwell during his revelations.
Fulcher had driven the criminal to a beauty spot and pleaded with him to give up Ms Callaghan’s location.
He invoked ‘Emergency Powers’ – usually used when there is a threat to life, like a terrorist attack – and asked Halliwell to help.
But it was ruled that he should have cautioned the then-suspect under PACE, which he knowingly failed to do.
Fulcher later said the situation was on a “knife-edge”, fearing that Halliwell might change his mind about showing them where the body was located.
Fulcher, now 54, was later found guilty of gross misconduct by a disciplinary panel, and was handed a final written warning.
He decided to leave Wiltshire Police in 2014 and had now said that he is still “bitter” a decade after the events.
He said: “What should have been a triumph became a disaster. It was an extremely painful period of time for a good three-plus years.
“The tragedy for me is that, quite clearly – and it’s not my romanticism – quite clearly there are other victims.
“As I have said time and time again, [Halliwell] abducted from a public place Sian O’Callaghan and murdered her within moments of her getting in his car.
“He’d killed Becky Godden eight year earlier.
“Everything about his MO, everything about the calls he received and made from prison – the notion that ‘police are investigating me for eight murders’, his own words.
“His trophy store at Ramsbury with 60 items of women’s clothing, everything about his history and behaviour indicates that we haven’t, and probably never will, get to the bottom of his full offending.
“And that in turn means there are any number of mothers and fathers who will never find their daughter again.
“I’m left with a very bad taste in my mouth – it’s the summary of it.”
Fulcher’s arrest of Halliwell was made into ITV drama ‘The Confession’ in 2019, and has been the source of much debate.
He has received support from some of the victim’s relatives, with the mother of Ms Godden campaigning to David Cameron, the Prime Minister at the time, for more protection from PACE for police.
But Fulcher still feels wronged by senior officers – and believes he may have been able to prise information about more victims from Halliwell if given the chance.
He said: “I’m still bitter and angry – nothing’s changed.
“If your daughter went missing tomorrow, I would not be confident that the police would do the right thing in preserving your daughter’s life.
“We don’t know [how many victims there are], but we should have done.
“If I hadn’t been so brutally abused by that set of circumstances there was a fighting chance Halliwell and I would have got to the bottom of all this.
“But, obviously, that moment is a very long time in the past.”
Asked if he regrets his actions, he added: “If I’ve saved a victim as a consequence of sacrificing my career, then I’m happy with that deal.
“It didn’t need to be this way. That’s my disappointment with the thing.”
Fulcher resigned in 2014 and quickly moved into conflict resolution, working to reform police forces in places such as Somalia and Libya.
He has now returned to the public eye after throwing his support behind former colleague Mike Rees, 55, who is standing for the role of Police and Crime Commissioner in Wiltshire.
The pair worked together on the Ms O’Callaghan case in Swindon 10 years ago.
Fulcher said of Rees: “He was willing to stand because he’s spent his entire life working for Wiltshire Police.
“He asked for my support, which I was more than happy to agree to. I’m more than happy to give my input if that helps in any way.”
Rees, who is standing as an independent, is aiming to tackle the perceived ‘watering-down’ of his local force due to austerity.
He told the Swindon Advertiser : “I don’t currently think [Wiltshire Police is] delivering the best service it can deliver.
“Police stations are closing, resources are lacking and I think the time’s right for someone to come in, who’s got an understanding of what the police service is about.
“You’ve got to go back to the basic role of a police officer.
“It’s about keeping the peace, preventing and detecting crime and protecting life and property. I think we’ve lost sight of that.”
Fulcher said he will be providing help to Rees as best he can, offering advice and support.