Bungling robber caught by DNA after he vomitted and victims offered him glass of water

Christopher Cummings, aged 30, could have got away with hundreds of pounds worth of jewellery and electrical items - but for DNA left on a small tumbler.

He was jailed for eight-and-a-half years after he admitted robbery at Birmingham Crown Court.

The court heard he burst into the home of the couple, both aged 90, and pinned the man to the floor in front of his horrified wife while an accomplice ransacked the property.

During the raid Cummings, who was high on drink and drugs, threw up and the couple kindly offered him a glass of water.

Incredibly, he was caught after police traced him using DNA extracted from saliva he left on the rim of the glass.

Forensics experts returned a match for Cummings on the police database who had previously been arrested for theft and dishonesty offences.

Jobless Cummings was arrested eight days after the robbery by officers who spotted him in Birmingham city centre.

He initially denied robbery but changed his plea on the first day of his trial and he was put behind bars for eight-and-a-half years on Friday.

The court heard Cummings raided the couple's home in Edgbaston, Birmingham, on the evening of April 4 last year.

Cummings and his accomplice – who has yet to be identified – made off with cash, jewellery, an iPad and a mobile phone.

The 90-year-old man suffered a cut head and bruising, whilst his wife was treated for shock.

Detective Constable Martina Millar, of West Midlands Police, said: "The couple answered the door at around 1pm on the day from two people claiming to be distant friends of their next-door neighbour and asking for a contact phone number.

"In fact it was Cummings and an associate checking who lived at the property and whether it was potentially a soft target – and at 7pm they returned, rushed inside and Cummings pinned the 90-year-old man to the floor.

"The victim said they smelled strongly of alcohol and during the raid Cummings was sick.

"Despite him putting this couple through a terrible ordeal they were kind enough to offer him a glass of water – but that turned out to be his undoing because we were able to swab the glass and obtain a DNA profile."

Richard Small, the force's Head of Forensic Science, said: "We're trialling kit that will allow us to obtain DNA information from samples in-house rather than sending them away for analysis – it means we could be looking at ID-ing offenders within hours and bringing them to justice more quickly.

"This was an interesting court case because no doubt many people would presume there was an abundance of DNA at the scene in Cummings' vomit.

"However, there would be relatively little of the offender's DNA contained within it – and would be contaminated with stomach acid and food – so the saliva would have provided a much better quality sample."