A "grossly offensive" image of WPP boss Sir Martin Sorrell and a female colleague could not be found on two laptop computers belonging to the Italian executive Sir Martin accuses of masterminding a hate campaign against him, a court heard today.

Computer expert Peter Sommer told the high court in London he had no evidence that the image was stored on either of the laptops owned by Marco Benatti, WPP's former "country manager" in Italy.

Nor was there evidence that Mr Benatti had received the image by email, Mr Sommer said.

The court heard that Mr Benatti had viewed a defamatory internet blog that Sir Martin accuses him of creating, making it one of his "favourites".

But there was no evidence that he had gone to the site until a link to it was sent to him by his lieutenant Marco Tinelli, the court heard.

Mr Benatti's barrister, Andrew Caldercott QC, said Mr Benatti had not accessed a second and third blog that repeated the same allegations about Sir Martin.

The gaps in the electronic paper trail emerged on the fifth day of a libel and invasion of privacy trial brought by Sir Martin against Mr Benatti and Mr Tinelli.

The case hinges on whether the two Italians can be proven to be the authors and distributors of the blogs and the image.

Sir Martin's lawyers believe they have the forensic evidence to tie Mr Benatti and Mr Tinelli to the allegations, which were first made in March last year, two months after Mr Benatti was sacked from WPP.

Mr Benatti and Mr Tinelli deny any responsibility for the blogs and the image.

The case continues.

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