James Alessi, a Caltrans representative who investigated the fatal incident for which David Attias stands trial, testified in court Tuesday.

Alessi, a member of the Caltrans Multi-disciplinary Accident Investigation Team, showed a diagram to the jury to indicate where Attias’ black Saab struck the five victims who were walking on the 6500 block of Sabado Tarde Road on Feb. 23, 2001. Alessi also showed where the victims landed, where Attias’ vehicle struck cars parked on the roadside and where the vehicle finally stopped.

Attias is charged with nine felony counts for the collision, including four counts of second-degree murder.

Using a methodology for calculating speeds involved in collisions between vehicles and pedestrians, Alessi estimated that Attias’ Saab struck the victims at a minimum of 53 miles per hour and a maximum of 63 miles per hour.

The sometimes graphic testimony evoked a noticeable reaction from some spectators.

“Attias maintained his course by refusing to brake,” Alessi said. “He struck one of the cars [parked on the side of Sabado Tarde Road with enough force to deploy the airbag.”

Jurors exited the courtroom as part of a demonstration by prosecutor Patrick McKinley, which was meant to visually convey the lengths of 152 feet and 207 feet, the distances two of the victims were thrown.

The trial continues this morning at 10 in department two of the Santa Barbara Superior Courthouse.