A “predator” who raped a teenager and murdered a woman whose bound and gagged body was found in a lake has been convicted decades after his “horrendous” crimes.
Serial attacker Donald Robertson was charged last year after a police cold case team found new DNA evidence linking him to the death of Shani Warren in April 1987.
The body of 26-year-old Ms Warren, who lived in Stoke Poges in Buckinghamshire, was found in Taplow Lake on the Easter weekend that year.
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.
Robertson, 66, did not attend his trial and the dock at Reading Crown Court was empty on Tuesday as a jury found him guilty of both crimes.
He was convicted of the false imprisonment, indecent assault and murder of Ms Warren between April 16 and 19 – her wrists having been tied with a car jump lead and ankles bound by a tow rope.
He was also found guilty of the kidnap and rape of a 16-year-old girl, who cannot be identified, on July 16 1981.
Police described “evil” Robertson as someone with a “long and horrific list of previous convictions” and said it is “a regret” there was not enough evidence at the time to charge him with the teenage girl’s rape in Farnham Lane, Slough.
Just days after being released by police in connection with that offence, Robertson raped a 14 year-old girl who had been riding her bicycle in Farnham Royal, a crime to which he pleaded guilty in October 1981.
In a similar vein, less than two months after attacking and killing Ms Warren and only a few miles from Taplow Lake, he raped a 17-year-old girl who was walking home having missed the last train.
He is currently behind bars for that crime, having been convicted in 2010 after the incident was reviewed by the police’s cold case team.
The prosecution said new DNA evidence was the “cornerstone” of the latest case against Robertson – with traces matching his found on the underwear of both victims as well as on a mouth gag used on Ms Warren.
Police said they were sorry it had taken so long to bring her attacker to justice, but that the case coming to court was down to advancements in forensic science.
Thames Valley Police’s major crime review team’s principal investigator, Peter Beirne, told the PA news agency: “In relation to Shani’s family I’d like to thank them for their support, thank them for their patience.
“I’m sorry that it took so long to bring Robertson before the court, but we’ve only been able to do that as a result of advancements in forensic science. It was not as a result of any lack of effort on behalf of the police.
“It was just that unfortunately, at that time, there was not the evidence to enable us to charge Robertson.”
Mr 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”.
He said Robertson’s failure to attend his trial “speaks volumes” to his character, labelling him “a coward, (who) wasn’t prepared to stand up and answer to the charges which were put before him”.
He praised the victim of the rape for her “strength of character” in going to court to give evidence during the trial.
He said: “I’d like to thank her for her bravery and courage in coming forward when we spoke to her, having to go through the ordeal of giving evidence before a crown court and also having to relive that horrific event which took place all those years ago.”
Robertson did not give evidence in his defence, and his lawyer called no witnesses but claimed another convicted rapist guilty of crimes around that time involving tying women up and attacking them could have been the culprit.
He also referred to evidence from a pathologist at the time of Ms Warren’s death stating she could have tied her own wrists and ankles, making it a suicide, and argued that even if a third party was involved, the possibility of someone falling into the water after having been tied up and assaulted, could not be ruled out.
But the prosecution said Ms Warren had not been suicidal and the jury took just seven hours and 18 minutes to convict Robertson of murder alongside the other charges against him.
Senior Crown Prosecutor Robbie Weber, of the Crown Prosecution Service, hailed advances in forensic science leading to “new compelling DNA evidence clearly linking Robertson to both crimes”.
He added: “This evidence underpinned the case that we presented at trial which has today resulted in guilty verdicts.”