http://news.bbc.co.uk/local/bristol/hi/people_and_places/newsid_8483000/8483532.stm
Video starts at 6.15
As they work their way through the 24 boxes of paperwork on the unsolved case, they will scan some 3,000 statements taken from the 16,000 people questioned, 70 of whom were arrested after her body was found on grassland near Bristol Zoo.
They are not currently linking Miss Carruthers' case with that of Joanna Yeates, but any similarities or links to suspects will be passed on to the investigation team immediately.
On January 18, 1974, Miss Carruthers left a 21st birthday party for her friend Sandra Hardyman at 8 Worcester Crescent.
The 20-year-old student teacher stepped outside, perhaps for a breath of fresh air and a stroll, not realising it would be her final walk.
The country was in the middle of an energy crisis at the time and only the most essential street lighting was on, so most roads were in pitch darkness.
Both women were third-year students at Bedford College of Physical Education and had travelled from Buckinghamshire that day to Miss Hardyman's home city.
There were about 40 people at the party – of all ages – and everyone seemed to be enjoying themselves. But just why Miss Carruthers decided to leave the party at about 10pm remains a mystery.
Miss Hardyman's godmother Jay Hunter said: "Glenis had stayed at Sandra's home before, so she knew some of the people there. She apparently didn't tell anyone when she left the party. I didn't know anything about it until Sandra told me that she was worried because she couldn't find Glenis.
"I suggested that she might be in another room but Sandra had said that she had looked and could not find her."
At the time, Detective Chief Superintendent Lewis, head of Bristol CID at the time, could only guess at why: "She may have been hot and needed a breath of fresh air. She may have felt lonely because everyone seemed to have a partner."
Another theory was that she went to make a call from a phone box near the Downs.
But whatever her reason for leaving, Miss Carruthers walked half a mile through the dark streets. At the time, Edward Heath's fight with the miners was at its height. For weeks, Bristol businesses and homes had been lit by emergency generators and candles during a rolling programme of power cuts so street lighting had been reduced to a minimum.
Miss Carruthers' distraught father William said after the inquest into his daughter's death: "I'm now convinced that but for the absence of street lighting, Glenis would have been alive today."
Miss Carruthers reached a grassy spot near a slip road between The Avenue and Northcote Road, with a telephone kiosk nearby. It appears it was there that she met her killer.
Zoo keeper Alf Elliott, who lived in Northcote Road, said he had spotted someone who fitted Miss Carruthers' description while he was out exercising his dogs.
He passed what he thought was a courting couple but when he passed them again the man got up and walked away, leaving the woman in the grass.
"I shouted to him 'Hey, what's your game?' He didn't reply and I repeated what I had just said. He just stared and went on his way," the zoo keeper said.
"I called the police straight away. I could not see the man very well as it was quite dark and a mass of hair hid his face."
When Miss Carruthers' body was found she was barefoot, her sandals lying close to her body.
In the exhaustive inquiry that followed, 175 detectives and officers questioned almost everyone in the area, including every pupil at nearby Clifton College.
A key piece of evidence was the shank of a pair of spectacles which might have belonged to the killer, found nearby. Every optician in the county was visited but no information was forthcoming about the wearer.
The lack of serious injury to Miss Carruthers surprised both the Ham Green hospital pathologist Derek Johnson and Mr Lewis.
He said: "The lack of a struggle, lack of injury, lack of anything to go on hampered our inquiries. One almost felt it was a mistake thinking this was a murder."
Examinations only discovered a small abrasion on her throat, suggesting the attack could be an indecent assault from behind. The official cause of death was "manual strangulation" but there was no evidence of a sexual assault. The suspect was 20 to 25 years old, had brown shoulder-length hair and was wearing a three-quarter length denim-type coat.
The unsolved case has always remained open.
Head of the police's Major Case Review Team, (MCRT) Detective Chief Inspector Mike Carter, has been leading the investigation for several years and started looking through the files again after police arrested a suspect in the Joanna Yeates case on December 30.
Miss Carruthers' brother Gordon and former detectives contacted DCI Carter within days of the announcement that Miss Yeates had been strangled, highlighting the similarity in the cause of death.
He was not specifically asked to look back at the case by the Yeates investigation team, led by DCI Phil Jones, but he has told the Evening Post that if any links between the cases are found they would be channelled into the Yeates murder inquiry.
Some of the files kept on the case are indexed but others will need a page-by-page examination of who was questioned by the five-strong team in order to find anything significant.
"If we come up with anything we'll put it into the team," he said. "Although we'll be doing this next week, the reality is we would be doing it at some stage in the future anyway. The case has never been closed and we continue to work to find Glenis Carruthers' killer."
In recent years, the main stumbling block for detectives has been the lack of DNA evidence from the Carruthers murder scene.
Thus far, there is no DNA available of her and no DNA profile of a suspect. The Carruthers case is one of a handful of unsolved murders – also including Philip Green in 1970, Mark Yendell in 1984 and Derek Grain in 1980 – that the team has invested Home Office funding in as the team tries to make a forensic breakthrough.
Earlier this year, the black beads Miss Carruthers was wearing on the night she was murdered were sent off for forensic testing, but results proved negative.
Fibres from her clothes were also sent off for examination and work is ongoing to see if DNA evidence could be gleaned from those.
All of the 25 long-term unsolved murders linked to the Bristol area have been reviewed in the past 18 months by the team, as well a number of rapes that they have solved using DNA evidence.
http://www.thisisbristol.co.uk/news/UNSOLVED-CASE-HOLD-KEY-MURDER/article-3079022-detail/article.html
