The Italian executive accused of distributing a "grossly offensive" image of WPP boss Sir Martin Sorrell and a female colleague would not have "stooped so low", a court was told today.

Marco Benatti, WPP's former "country manager" in Italy, also had no role in the creation and distribution of a series of internet blogs that defamed Sir Martin, his barrister told the High Court in London.

Sir Martin is suing Mr Benatti and his lieutenant Marco Tinelli for libel, and also claims the image of him and WPP's chief operating officer, Daniela Weber, was an invasion of privacy.

The court has heard how Mr Benatti was sacked by WPP in January 2006 after his 20-year friendship with Ms Weber broke down and he fell out acrimoniously with Sir Martin.

"[Mr Benatti's] case is simply that he would never stoop as low as this jpeg [image]," his barrister, Andrew Caldecott QC, told the court.

"He also says in relation to the blog he would never have included, as the blog did, an untrue allegation that Ms Weber had had an affair with him."

Opening his defence of Mr Benatti today, Mr Caldecott likened Sir Martin's case to a "bowl of spaghetti milanese: jumbled pieces of evidence superficially tasty in parts but whose individual strands are muddled and lead nowhere or to ends that are simply obscure".

Mr Caldecott said there was no evidence of collaboration between Mr Benatti and Mr Tinelli, the chief executive of Italian advertising group FullSix, in which WPP has a 20% and Mr Benatti is also a major shareholder.

He said Mr Tinelli should not be seen as Mr Benatti's "poodle", who was willing to assist in a hate campaign that was not in his own interests.

Mr Tinelli had in fact tried to minimise bad blood with WPP, he said, while publishing the blog would have been "an own goal of quite spectacular proportions".

"What could FullSix possibly gain by climbing into the ring with Sir Martin and WPP?" Mr Caldecott said.

"Mr Tinelli is a young businessman of dynamism and vision, he is not a kamikaze pilot under the remote control of Mr Benatti.

"He saw FullSix's interests lay in distancing themselves from this dispute and he foresaw the damaging consequences which would follow if FullSix started to mix it with WPP."

He said Mr Tinelli also lacked the technical skill to conceal the origin of the blogs on his computer.

Sir Martin's legal team were painting an implausible picture of someone who "veered from Professor Moriarty to Inspector Clouseau in a matter of moments," Mr Caldecott said.

Mr Caldecott added that the level of "quite sophisticated, idiomatic" English used on the blogs made is less likely that the Italians were involved.

The blogs included phrases such as "what makes Don Martino tick" and "Don Martino shapes the world from his BlackBerry".

Mr Caldecott said there was evidence of a "malign presence" within FullSix who could have been the source of the blogs and the offensive image.

He said Mr Tinelli had received an email after the publication of the blogs and image, sent by someone called "WPP Italy Watchdog Committee", that included material criticising Mr Benatti.

The email had also reached FullSix's clients such as Alfa Romeo and Alitalia.

Although the sender was never identified, the internet provider used was registered to FullSix, Mr Caldecott said.

The case continues.

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