Police could not find any fingerprints on Dr Kelly's 'suicide' knife
The Hutton Inquiry into the death of the Ministry of Defence weapons expert ruled that he slashed one of his wrists with a blunt garden knife and took an overdose of pills.
But the campaigning Liberal Democrat MP Norman Baker has carried out his own investigation after forensic experts questioned the official version of events.
The Lewes MP made the discovery after submitting a Freedom of Information request to the force.
The lack of fingerprints is especially strange as police records also revealed the germ warfare expert was not wearing any gloves when he died – nor were any found at the scene of his death.
Mr Baker said: 'It is one of the things that makes me think Dr Kelly was murdered.
'The angle you pick up a knife to kill yourself – there would be fingerprints. Someone who wanted to kill himself wouldn't go to the lengths of wiping the knife clean of fingerprints.
'And wearing gloves would seem very odd when you are about to cut your own wrists. It is very strange.'
Mr Baker is also suspicious about the cut to Dr Kelly's wrist.
It completely severed a tiny blood vessel called the ulnar artery, which is deep in the wrist and protected by nerves and tendons.
It is highly unlikely anyone without a blood-clotting defect would bleed to death from a single cut to this artery.
It would have required unusual force to cut through the tendons, particularly with a blunt gardening knife, and it would have been very painful.
To ascertain just how unusual the injury was, Mr Baker asked the Office of National Statistics how many people in the UK died in 2003 from a cut to the ulnar artery.
He was told that Dr Kelly was the only one. The scientist was found dead in woodland near his home in Southmoor, Oxfordshire, in July 2003 after becoming trapped at the centre of a vicious war of words between the Government and the BBC.
Blunt: A gardening knife similar to thr one found by the body
His death came days after he was unmasked as the source of a Today programme report alleging Labour had 'sexed up' a dossier outlining the case for war in Iraq.
The document had famously claimed that Saddam Hussein could launch a nuclear or biological weapons strike on Britain within 45 minutes.
Dr Kelly, a father of three, was grilled on TV by MPs on the Foreign Affairs Select Committee.
His widow, Janice, claimed her husband had been put under 'intolerable pressure'.
But Lord Hutton exonerated the Government and ruled that Dr Kelly's death was a suicide – leading to accusations that the inquiry had been a whitewash.
Independent doctors have pointed to discrepancies in the post-mortem examination results.
They say neither the cut to Dr Kelly's wrist nor the drugs he took were enough to kill him.
Friends and relatives said the doctor had shown no suicidal tendencies, and had been looking forward to his daughter's wedding.
However, Mrs Kelly remains convinced that her husband killed himself and refused to comment on the latest development.
A Thames Valley Police spokesman said: 'It has been confirmed that there were no fingerprints on the knife whatsoever. This however does not change the official explanation of his death.'