A California Highway Patrol accident investigator Wednesday knelt below a 12-foot diagram to show how a northbound car crossed double-yellow lines, passed two vehicles and returned safely to its lane before causing a head-on collision of two other vehicles.

Multidisciplinary Accident Investigation Team officer Robert Shaw swept his hands back and forth across the bottom of the diagram, suggesting the speed of the Acura MDX driven by Danny Anderson as it passed a 2009 Toyota Camry and a gray Ford Windstar minivan before passing back over the double yellow lines.

“I tried to keep it as simple as possible,” Shaw said.

Pointing to color-coded vehicles divided into second-by-second intervals along the diagram, Shaw said the reconstruction began at zero — right when Anderson began to pass, but before he actually crossed into the oncoming lane.

Two seconds later, a 2002 Lexus RX300 rounding a southbound curve in J-59, would be visible to Anderson.

At 3.5 seconds, Anderson would still be 16 feet from the rear of the 2009 Toyota Camry, Shaw said, and still would be able to return back into the northbound lane.

The distance between Anderson’s vehicle and the 2002 Lexus RX300 was narrowing quickly, he said, as the Acura MDX accelerated to safely complete the pass without impacting any other vehicles.

“It’s continuing to get faster and faster as we go,” he said.

At 5.25 seconds, Anderson would be alongside the Camry, driven by Dorothy Eisemann, 68, who testified on Friday she watched a white vehicle “whoosh” by her.

Soon after, tire friction marks and disturbed gravel near the accident site indicated that Trista Hoffman, 16, the driver of the Lexus, would have responded to the oncoming vehicle and veered off the road, Shaw said.

Shaw indicated that Trista Hoffman would have said, “I’ve got to do something, there’s a car coming at me.”

At 7.45 seconds, Anderson would have passed 16 feet ahead of the gray the Ford Windstar and began to move back across the double yellow lines.

“Prior to completing his pass,” Shaw said, Anderson would have seen the Hoffman vehicle coming directly towards him. But before the return to the northbound lane was completed, Shaw said, the Camry and the Lexus would have collided head-on.

At 8.78 seconds, the two vehicles crashed, he said. At 9.12 seconds and a total of 957.77 feet traveled, Anderson would have passed and returned to the northbound lane.

As Shaw presented his conclusions, Judge Donald Segerstrom stood alone on one side of the jury box. Tom Johnson, lawyer for the defendant, stood along the opposite side of the jury box with two alternate jurors and multiple members of the public that were unseated due to the position of the diagram.

Anderson stared at thediagram on a computer in front of him.

District Attorney Laura Krieg asked Shaw, who was established as an expert witness in accident reconstruction, what he believed caused the accident.

“Mr. Anderson’s passing over the double yellows, approaching a hill and a curve in the roadway,” Shaw responded.

Krieg also emphasized from Shaw’s research that Anderson could not have seen the collision as a white flash in his rearview mirror from either a half or a quarter mile away to the south as he previously claimed to CHP officer Jason Austin during a recorded interview.

“There’s no way you're seeing anything at the collision scene from this vantage point,” Shaw said.

Tina Hoffman, 51, and her daughter Trista Hoffman in the Lexus, were pronounced dead at the scene following the collision. Backseat passengers of the Lexus, Dillon Hoffman, 17, sustained two broken legs, and Annie Johnson, 16, sustained brain hemorrhages. Reinholt John Eisemann, 72, a passenger in the Camry, died following the collision.

CHP - Sonora area Officer Steve Griefer testified that he spoke to Danny and Diane Anderson at the scene of the accident, but neither expressed that they were in involved.

“He stated he arrived on scene and began rendering aid,” Griefer said. “Had I been notified by any involved, any person, I would have made note of that like I was there yesterday.”

Griefer said the couple both appeared to have a “thousand yard stare” which indicated that they were “disconnected” and “that they had seen a traumatic event,” he added.

Griefer prepared a supplementary report of his contact with the Andersons, which was submitted on Feb. 16, 2017, the same day as a report prepared by former CHP Sgt. Shawn Snyder, who testified on Friday.

The explanation of the accident reconstruction, which lasted multiple hours under cross examination, was derided by Johnson as the product of false approximations and assumptions made by MAIT.

“When you’re giving us your finding, you’re taking an estimate and giving us a concrete number,” Johnson said.

When establishing the mathematical parameters of the reconstruction, Shaw said, he had to make certain estimations about the time of the accident based on surveillance footage from the Houseboat Mini Mart, witness statements, and objective evidence.

During part of the explanation, Lt. Commander of the CHP - Sonora office, Shane Ferreira, sat in the rear of the public section. Ferreira was not the commander at the time of the accident and was hired in February 2017.

Shaw, who said he examined the Camry, was able to access an airbag control module within the vehicle to perform a “crash data retrieval” of the Camry’s changing speeds five seconds before the impact.

At the beginning of the data retrieval, the Camry shifted between 47.2 miles per hour, then slightly accelerated to 48.5 miles per hour before dropping to 47.2 miles per hour and eventually at 44.7 miles per hour just before the impact with the Lexus, Shaw said.

The distance between the Anderson Acura and the Camry, and the distance between the Camry and the gray Ford Windstar was approximated based on the Houseboat Mini Mart video at 54 feet, or about three to four car lengths.

CHP - Sonora Area Officer Jason Austin was recalled for testimony on Wednesday and revealed additional surveillance footage from the Foothills Self Storage facility in La Grange. The surveillance footage, approximately two miles south of the Houseboat Mini Mart and minutes before the accident, shows the same procession of vehicles featured in the other surveillance video, but with a more than 40 second gap between the Eiseman Camry and Anderson’s Acura.

“It’s the same order. The spacing of the vehicles is different,” Austin said.

Johnson argued that time, weather conditions and potentially untrue statements from witnesses could have degraded the legitimacy of the MAIT report. He said heavier-than-normal precipitation that winter could have altered tire marks, and noted many months had passed since the accident before Shaw went to the scene on June 6, 2017 with Dorothy Eisemann, who showed him where the Acura passed her.

Other approximations made for the MAIT report included the speed of the Hoffman Lexus at 50 miles per hour based on a statement from Dillon Hoffman and Shaw’s analysis of the crash site, Shaw said, and the acceleration of Anderson’s vehicle based on a report from Car and Driver magazine.

“Every variable that gets changed changes the ultimate equation,” Johnson said, but Shaw responded that it was the “totality” of the analysis that led to his conclusion.

Anderson squinted toward Shaw during a line of questioning that suggested the Acura could have completed the pass safely if the start of the movement began further south down the road. When Shaw denied the credibility of that claim, Anderson grimaced and shook his head.

Shaw also noted to Johnson that he had completed calculations that debunked the possibility of the white crossover vehicle behind the Acura being able to complete the pass.

Segerstrom disallowed the line of questioning to be pursued by Krieg because the information was not shared to the defense, but during a brief session of the trial closed to the jury, Shaw said only a “rocket car” would have been able to complete the pass from that distance to the crash site.

CHP - Capistrano Area Officer Robert Rand also testified on Wednesday that he took multiple photos of the Acura on Dec. 13, 2016, after it was located at Paradise Automotive Group in San Juan Capistrano.

Anderson has been charged with three felony counts of vehicular manslaughter with gross negligence with enhancement charges of fleeing the scene, one count of hit-and-run resulting in death or serious injury of six people, one count of reckless driving causing specific injury or death for the three fatalities, and misdemeanors destroying or concealing evidence and obstructing a police investigation.

The trial will resume at 8:30 a.m. Thursday in the Tuolumne County Superior Court.

Contact Giuseppe Ricapito at (209) 588-4526 or gricapito@uniondemocrat.com . Follow him on Twitter @gsepinsonora.