03:37PM, Tuesday 17 May 2022
Shani Warren was found dead in Taplow Lake in April 1987
A serial sex offender has been found guilty of the murder of Shani Warren in 1987, as well as her indecent assault and false imprisonment.
Donald Robertson, 66, formerly of Slough, was found guilty by a unanimous Reading Crown Court jury today following a two-week trial, which took just over seven hours to return a verdict.
He was also convicted of the rape and kidnap of a 16-year-old girl, who cannot be named for legal reasons, in 1981.
Ms Warren, who was 26 at the time of her death, was found tied and gagged in Taplow Lake on April 18, 1987 by a dog walker.
The day before, on Good Friday, she was cutting the grass of her garden in Neville Close, Stoke Poges
At around 6pm, Shani was seen loading bags of the grass cutting into her car, a black Vauxhall Cavalier. She then drove away from her house, presumably to dispose of the grass cuttings.
Following the discovery of her body, an investigation was launched by police and the death was treated as suspicious.
Pictured: Ms Warren's Vauxhall Cavalier car at the scene of her murder in 1987
A pathologist believed at the time that she had taken her own life but, when Thames Valley Police recently reinvestigated the case, they discovered Robertson’s DNA was present on items found on Ms Warren, including her bra and a gag placed around her mouth.
The jury was told the chances of the DNA on the bra not being Robertson’s was one in 26million - while forensic studies on the mouth gag revealed the chances of the DNA not being Robertson’s as one in a billion.
In relation to the rape charge in 1981, a detailed study on the underwear the victim put on after the attack was carried out in 2021, revealing a DNA profile matching that of Robertson.
Robertson (below) – who was not present throughout the whole of the court proceedings – is already serving a life sentence for a previous sexual offence.
The jury learned during the trial that the 66-year-old was a prolific sexual predator during the 1970s, 1980s and 1990s when he was convicted of a series of offences including burglary, attempted rape, kidnap and rape.
Reacting to today’s verdict, Senior Investigating Officer for the case, Principal Investigator Pete Beirne, called Robertson a ‘coward’ and thanked Ms Warren’s family for their bravery after 35 years.
“We are very pleased with the verdict of the jury,” he said. “We’re relieved that after 35 years we are finally able to tell Shani’s family that she was murdered.
“We are always mindful of the fact that what we are doing will potentially help the family but it will never replace what they have lost.
“You do not approach the victim’s family until you are making lee-way, so it was at that point when you had evidence pointing towards Robertson that we took the decision to make contact with Shani’s brother.”
Police tape at the scene in April 1987
PI Beirne added that while the case attracted mass media interest at the time, he and his team were under less pressure as they re-examined the case in recent years.
“Shani’s case was subject to a reinvestigation in 1997/98 when it was linked to a series of offences under Operation Lynx, which aimed to crack down on historic sexual offences,” he said.
PI Beirne added that the forensic studies on Ms Warren’s bra and the mouth gag were carried out in 2020.
He thanked Ms Warren’s family for their bravery during the Reading Crown Court trial, which began on April 27.
“I would like to thank them for their help and support. It has not been easy for them because it brings back to the fore the horrendous events that took place 35 years ago,” PI Beirne said.
“We have got the offender, but unfortunately the family have had to live with this for 35 years.”
He thought he’d got away with a murder he’d committed 35 years ago, but he was wrong...— Thames Valley Police (@ThamesVP) May 17, 2022
In the last few minutes, Donald Robertson has been convicted of the brutal murder of Shani Warren in 1987 and the rape of a girl in 1981.
For more https://t.co/e2xHgVyhyJ pic.twitter.com/OA2pJCKSNb
Police added their thanks to the victim of the rape and her family for their help in securing convictions against Robertson.
“I want to thank her for her courage and for coming to court to give evidence,” PI Beirne said.
“I apologise that we had to bring these memories back to her mind – to have to go to court and relive the most horrendous thing that has ever happened to her must have been terrible.
“We want to thank her for her strength in helping us get these convictions.”
PI Beirne had a message for Robertson and other historic sexual offenders in light of the jury verdict, with police now able to access more vigorous DNA evidence to crack down on criminals.
“Throughout his adult life Robertson has been a threat to women, he is a sexual predator who has got a horrendous list of convictions against him.
“He was a coward and would not even appear in court to listen to the offences.
“Unsolved cases will always remain open as far as TVP is concerned.
“I want people who have committed these serious offences to realise we are still working on these cases and will be knocking on their doors soon."
An aerial shot of the scene a few days after Ms Warren's murder
Robbie Weber, of the Crown Prosecution Service, added: “Robertson is a dangerous and deadly predatory sex offender who attacked women over almost three decades, using violent threats to get what he wanted.
"In the case of Shani Warren, he went as far as to take her life.
“Advances in forensic science led to a breakthrough in the unsolved cases of Ms Warren’s death and the sexual attack on another young girl, with new compelling DNA evidence clearly linking Robertson to both crimes.
"This evidence played a vital part in the case that we presented at trial which has today resulted in guilty verdicts.
“Our thoughts are with Ms Warren’s loved ones and the other victim in this case who have waited many years to see justice served.”
Robertson will be sentenced at Reading Crown Court on Thursday afternoon.
Closures are planned on the M4 between Langley and the M25 this weekend for smart motorway works.