'Predatory' sex attacker found guilty of murdering Shani Warren 35 years ago

Watch: ITV News Meridian's Derek Johnson reports on the police investigation spanning the last thirty years

A man has been found guilty of the murder of Shani Warren, who was found bound and gagged in a lake in Buckinghamshire in 1987.

Donald Robertson, 66, has also been found guilty of kidnapping and raping a 16-year-old girl in 1981.

Robertson was convicted by unanimous verdict at Reading Crown Court today (May 17), decades after his "horrendous" crimes.

It took jurors just seven hours and 18 minutes to reach their verdicts in the trial of Robertson, who did not attend.

Following the verdict, Shani's brother Stephen Warren said: "We cannot imagine what the last moments of Shani’s life must have been like, but you may agree that no punishment is enough for her attacker; a psychopath and a coward who lacked the courage to attend court, or even to give evidence via a live link.

“As you can imagine, the loss of Shani left a gaping hole in the family. Not just of a central member and surely its brightest light, but of a force of energy, hope and positivity.

"Shani, you were loved so much, and we have all, so many times, wished so hard that we could have – and would have – protected you on that terrible day."

Ms Warren’s body was found at the edge of Taplow Lake where her wrists and ankles were bound and she was gagged. 

Her car had been abandoned in a layby on the A4, with bin bags containing remnants of grass from Ms Warren having recently mowed the lawn, and an Easter egg in the driver's footwell.

A pathologist concluded that she had died from drowning, with a strong possibility of strangulation beforehand.

It was his opinion that Shani died by suicide, as there were no defence marks or evidence of sexual assault.

However Ms Warren’s death was investigated as suspicious, but there was not enough evidence for the police to charge anyone. An inquest at the time concluded with an open verdict.

Six years earlier, a 16-year-old girl was attacked and raped as she was walking home in Slough. Robertson was arrested at the time but released when the victim did not point him out during an identity parade.

Watch: Donald Robertson is asked by police if he'd ever been to Taplow Lake where he replies: "No...not fishing."

Advances in forensic science

In 2007, the Thames Valley Police’s cold Case team was set up and forensic examinations in relation to Shani’s murder were carried out, but no DNA from a suspect was found.

Further tests were then carried out between 2019 and 2020 by forensic experts on items from the murder scene, including a cloth that had been used as a mouth gag on Shani, and DNA material from Shani’s bra.

The DNA found on these items was compared with the National DNA database, and provided a positive match with Donald Robertson.

Robertson was already serving time in prison for a cold case involving the kidnap and rape of a girl in Slough in June 1987.

The team were also able to link Robertson to the rape of a 16-year-old girl in Farnham Lane, Slough, in July 1981.

DNA from clothing from the victim was tested again and the results matched Robertson’s DNA profile.

On 22 June 2021, Robertson was arrested on suspicion of the murder of Shani and the rape of the 16-year-old girl.

On 26 November the same year, Robertson was charged with the murder, indecent assault and false imprisonment of Shani Warren, and the kidnap and rape of the 16-year-old girl.

'A sick and depraved individual'

Head of the Major Crime Review Team and Principal Investigator, Peter Beirne, branded Robertson an "evil and dangerous" man and a "predator" who had attacked women and girls "throughout his adult life", subjecting them to "the most horrendous acts".

Mr Beirne said: "In both of these cases the victims were put through terrifying ordeals by Robertson and I only wish that he could have been made to pay sooner for his abhorrent crimes.

“It is clear from Robertson’s previous offending that he is a sick and depraved individual who would take any opportunity available to him, to approach young girls and women in order to sexually assault them.

“We will never truly know why Robertson murdered Shani on that Easter weekend in 1987, perhaps because she defended herself against his attack.

"Robertson, who is already serving time for other sexual offences, did not have the courage or decency to attend his trial and to answer for his crimes, for which he will soon be sentenced."