Chris Halliwell's daughter has appeared on ITV's Daybreak asking her father to give "justice" to the family of the second woman he killed.
Swindon taxi driver Chris Halliwell has been jailed for the murder of Sian O'Callaghan but is he guilty of the murder of other women?
It was a fluke, in a way, that Halliwell was ever caught. But it also needed some good detective work.
The MP for South Swindon has called for the Police and Criminal Evidence (Pace) Act guidelines to be re-examined after murderer Christopher Halliwell escaped justice for a second killing.
The taxi driver led officers to the bodies of Sian O'Callaghan and Becky Godden but a senior officer's failure to caution him and to deny him a solicitor meant the murder charge in Miss Godden's case had to be dropped.
Halliwell was jailed for life after admitting Miss O'Callaghan's murder.
Speaking in the Commons, Robert Buckland said the errors meant the family of Becky Godden have not received justice and it would be timely to look at the guidelines governing the detention and questioning of suspects.
A taxi driver has pleaded guilty to the murder of Sian O'Callaghan, who'd gone missing after a night out in Swindon last year. Christopher Halliwell admitted sexually assaulting her and stabbing her before dumping her body.
Today Bristol Crown Court heard Halliwell had been cruising around Swindon that night deliberately looking for a victim. However it's emerged that police were not able to proceed with another murder charge because of a legal mistake.
Our Wiltshire reporter Robert Murphy has been following the case and reports from Bristol Crown Court.
48-year-old Christopher Halliwell has been sentenced to life imprisonment for the murder of Sian O'Callaghan.
The taxi driver pleaded guilty to the murder of the 22-year-old in March last year.
Robert Murphy looks back at the police investigation:
Swindon taxi driver Chris Halliwell has been sentenced to life imprisonment for the murder of Sian O'Callaghan.
Pros: Halliwell was minicab driver. He stopped her as she left night club. He took her to Savernake Forest where he stabbed her.
Halliwell had clocked off his shift. & turned off his cab tracking device. CCTV shows him cruising streets 'in circular movements...'
... Before abducting Sian. He makes 4 or 5 passes. CCTV shows him passing Sian, turn around and stop. Glare of headlamps distorts image