Christopher Halliwell's 'lenient' murder term is appealed
An appeal is to be launched into the "lenient" sentence of a taxi driver who murdered an office worker in Swindon.
Christopher Halliwell was sentenced to life with a minimum term of 25 years for the murder of Sian O'Callaghan.
But the Attorney General, Dominic Grieve, has now applied to the Court of Appeal to establish whether the sentence in October was too lenient.
Nick Hawkins, from the Crown Prosecution Service, said it was referred after "careful consideration".
Miss O'Callaghan was abducted by Halliwell after a night out in Swindon and taken to Savernake Forest where he murdered her.
Her body was found several days later close to the Uffington White Horse in Oxfordshire.
Halliwell also led police to the body of Becky Godden shortly after he confessed to killing Miss O'Callaghan.
But he was not prosecuted over Miss Godden's death after a judge ruled detectives ignored arrest guidelines.
Following his arrest, Halliwell was not taken to a police station to be read his rights by Det Supt Steve Fulcher.
Mrs Justice Cox later said Det Supt Fulcher's decision to ignore guidelines in the Police and Criminal Evidence (Pace) Act was "significant and substantial".
It led to Halliwell only facing charges over the murder of Miss O'Callaghan and not Miss Godden, also known as Becky Godden-Edwards, who had been missing for eight years.
Det Supt Fulcher said he wanted to "appeal to the killer's conscience" but Mrs Justice Cox said the move was "designed to persuade the defendant to speak".
Since the case, Wiltshire Police has apologised to Ms Godden's family while Halliwell's daughter has appealed to him to tell the family what happened.