ITV drama A Confession left viewers horrified tonight as the case against killer Christopher Halliwell on the murder of Becky Godden-Edwards collapsed in court.
And in unearthed letters written from his prison cell, Halliwell admitted that he told DS Fulcher from the witness box that he enjoyed ruining his career.
The series, which stars Martin Freeman, tells the real-life story of Fulcher deliberately breaching police procedure and protocol to catch the killer.
Halliwell confessed to killing Sian O'Callaghan, 22, who went missing after a night out in Swindon in March 2011 after being cornered by police.
Halliwell admitted that he had killed Sian and led them to her body. However he then turned to DS Steve Fulcher, who was leading the investigation, and asked whether he "wanted another one".
The killer told them where he had buried Becky back in 2002-2003.
However despite his confession, the double murder investigation became incredibly complicated because Halliwell had not been reminded of his rights by DS Fulcher.
This meant that Halliwell couldn't be held to account for killing Becky.
The taxi driver killer was eventually convicted of murdering Becky in 2016 - 13 years after killing her.
Since his conviction, Halliwell has written many letters while serving time in Long Lartin prison in Worcestershire.
In 2016, the Sunday Mirror reported on the vicious remarks he made about Fulcher in the letters.
He wrote: "While he [DS Fulcher] was in the witness box I said to him that it was a pleasure ruining his career.
"I’ve got no regrets on that point. His one and only mistake was he threatened my kids and he’s paying for it."
*A Confession returns next Monday at 9pm on ITV
