A BOLOGNA law professor yesterday electrified the opening day of the trial arising from the death of Ayrton Senna by demanding a ruling that would undermine the entire proceedings.

In an impassioned harangue, Luigi Stortoni, counsel for the Williams team's designer, Adrian Newey, said his client's rights had been "blatantly violated" during the investigation As a result, he argued, the judge should declare that the bulk of technical evidence gathered by the prosecution was inadmissible. Newey had been questioned as if he were a witness when, in fact, he was a suspect. And "unbelievably and gravely", he had not been cautioned until the very day he was indicted last December.

"He had the right to be notified before being put before this court for a trial of this importance in which he would be accused of being the killer of Senna, his friend," said Professor Stortoni, his voice ringing with indignation.

It is a keystone of the Italian legal system that suspects are formally notified when they come under investigation so they can hire a lawyer. Newey's counsel said his client's name had been added to the list of suspects more than seven months before he was told.

Adrian Newey is among six -people accused of contributing to the Brazilian driver's death at the San Marino grand prix here three years ago. Senna's car hurtled off the track, over a verge and into a wall.

Frank Williams and his technical director, Patrick Head, are charged with "having modified, acting with negligence and imprudence, the steering column of the vehicle". The adjustment, for which Newey is said to have been responsible, was "badly designed and badly executed".

But Oreste Dominioni, the lawyer representing Head and Williams, said in a recess: "We are absolutely sure the steering column broke after the crash, and was not the cause of it."

A court official yesterday read out a list of 44 witnesses the prosecution intends to call. Among them was Damon Hill. It is still unclear whether Frank Williams, who was not in court yesterday, will give evidence. His Italian counsel said he expected his client to be present when the prosecution sets out its case next month.