David Coulthard told a court in Imola yesterday he has never doubted the integrity of the Williams Formula One team, despite Ayrton Senna's fatal accident in the 1994 San Marino Grand Prix. Six men, including team chief Frank Williams, are accused of manslaughter over the death of Senna, who crashed after flying off the track in his Williams car.

Coulthard, who now races for McLaren-Mercedes, was a test driver for Williams at the time of the high speed crash and took over from Senna for much of the remaining 1994 season.

"After the accident I had no doubts whatsoever over the integrity of the car and the people in the design team," Coulthard said in video footage shot earlier this year which was shown to the trial judge during yesterday's session.

Coulthard was present in the courtroom while the video was played. The film showed him sitting in the cockpit of a Williams as he demonstrated the considerable flexibility of the steering wheel.

State prosecutors believe that the accident was caused by a poor weld on Senna's steering column, which, they allege, snapped when the three-times world champion started to turn the notorious Tamburello curve forcing him to fly off the track.

"My view of the Williams Grand Prix team is very similar to that of many people who have a great deal of respect for them," Coulthard said.

Williams is due to give evidence in the case today, making his first appearance at the courtroom since the trial started back in February.

Alongside him are likely to be co-defendants Patrick Head, Williams' technical director, and Adrian Newey, the team designer at the time of the accident.

Three track officials have also been accused of manslaughter. All deny the manslaughter charges.