Christian Newman, 28, from Reading, Berkshire, had always denied attacking the 26-year-old in June 2002 as she slept at the house near the River Thames and said sex was by mutual consent.

At Reading Crown Court on Thursday, the Crown Prosecution Service (CPS) said it would not be taking its case any further after it was revealed that the alleged victim had lied about her relationship with Mr Newman.

Prosecutor Sandra Stanfield said text messages recovered from a mobile phone had shown the pair, who met as school friends, did have a closer relationship than the victim had claimed.

She said police had been in the possession of the contents of the down-loaded text messages.

Accused walks free

Had the CPS been aware of all of their contents, the case "may never have been brought at all", she said.

According to Miss Stanfield, the whole case had hinged on the idea that the victim had not had a relationship or feelings for Mr Newman, and she was trying to keep her distance.

She told the jury: "This puts a completely different complexion on it.

"We will not continue to put any further evidence and I would suggest that Mr Newman should not spend one minute longer in danger of losing his liberty."

Judge Charles Elly said it was unusual but he would have to direct the jurors to acquit Mr Newman.

The jury immediately returned verdicts of not guilty against both counts of rape and indecent assault.