London , England ( CNN ) -- A British man who strangled his wife in his sleep while dreaming that she was an intruder walked free from court Friday after the case against him was withdrawn , prosecutors said . The UK 's Crown Prosecution Service requested that the case against Brian Thomas , who killed wife Christine while they were on vacation in 2008 , be dropped due to a `` unique set of circumstances . '' Thomas , 59 , of Neath , South Wales , had been on trial for murder at Swansea Crown Court , with prosecutors seeking a verdict of not guilty by reason of insanity that would have resulted in psychiatric custody . But they said a closer study of evidence led them to believe the defendant should be released without further action . `` We have duty to keep cases under continuous review , and following expert evidence from a psychiatrist it was suggested no useful purpose would be served by Mr Thomas being detained and treated in a psychiatric hospital , '' prosecutor Iwan Jenkins said in a statement . Jenkins said that there had never been any doubt that Thomas caused his wife 's death , but the prosecution accepted evidence from experts on sleep disorders that indicated he should not be convicted of murder or manslaughter . `` We therefore have offered no further evidence and asked the jury to return a simple verdict of not guilty . '' The court erupted in shouts of `` yes '' as family members greeted the outcome with jubilation , according to the UK Press Association . `` The death of Christine Thomas was thoroughly investigated by Dyfed Powys Police . Investigations continued after Mr Thomas was charged and involved the instruction of experts in several fields , '' Jenkins said . `` I must emphasize that the circumstances of this case are almost unique in the UK and there have been fewer than 50 instances recorded worldwide . It is only because of highly sophisticated tests carried out by sleep experts that Mr Thomas 's condition could be confirmed . `` Our thoughts remain with the family of Brian and Christine Thomas , who have remained dignified throughout this difficult time . '' The brief trial , which opened Tuesday , heard that Thomas killed his wife while the pair were taking a camper van vacation in western Wales , PA reported . One night , Thomas -- who experts said may have been suffering worsening dreams due to withdrawal from anti-depressants -- experienced a violent nightmare in which he attacked and fought an intruder and got him in a headlock , only to wake and find he had strangled his wife . Dismissing the charges , High Court Judge Justice Davis described Thomas as a `` decent man and devoted husband '' who bore no responsibility for his wife 's death , PA reported . Thomas 's brother Raymond Thomas said the family were `` delighted '' by the outcome , the news agency said . `` He has always been a loving husband and a family man , '' he said. `` This was a tragic , tragic episode and we are all very emotional . ''
Prosecutors described trial involving Brian Thomas as a `` unique case '' Thomas killed wife during a bad dream while pair was vacationing in 2008 . The couple had been married for two years and were expecting their first child when he shot her to death at the couple's home on July 1, 2008.