Vikki Thompson went missing in Ascott-under-Wychwood, Oxfordshire, while walking her dog on 12th August 1995. The dog returned home without her, raising the alarm. After a frantic search, she was found alive but badly beaten - she died six days later in hospital.
Local man Mark Weston emerged as the prime suspect, and the Police set about building a case against him, amassing enough evidence to charge him with the murder. When the case went to trial, however, Weston was found not guilty by the jury.
A decade after the murder of Vikki Thompson, the double jeopardy law was changed in the UK in 2005, allowing a person to be tried for the same crime twice; the Police decided to look at the case again as part of a cold case review.
Weston's boots were resubmitted for testing and, due to the scientific advancements in the intervening period, tiny traces of blood were found on the boots. The blood was a match to Vikki Thompson.
In 2009 Weston was arrested again and faced another trial, and this time he was found guilty. The first time that the double jeopardy legislation was used to secure a conviction.