Jurors who will sit in judgment of former pastor Howard "Doug" Porter got a second lesson in collision reconstruction Monday in Stanislaus County Superior Court, when a prosecution expert challenged a defense expert's claim that speed caused a wreck that killed Frank Craig.
Both engineers made assumptions based on measurements and photos taken by crime scene investigators more than four years ago along the Ceres main canal, near Swanson Road in Hickman.
So the jury has heard differing opinions on a host of technical matters, such as whether a dirt berm could cause a GMC Sonoma to vault off the embankment, the truck's likely trajectory as it headed into the water and how much the truck rotated before it came to rest on the canal floor.
The bottom line: The defense expert said Porter must have been driving 52 mph to 63 mph when Craig's truck careened off the embankment and landed in the water, but the prosecution expert said the truck could have been going no more than 28 mph.
Michael Varat of Keva Engineering of Camarillo, who was called as a rebuttal witness after the defense rested its case, said he can explain how the wreck happened, not why.
"The driver steered the vehicle to the left," he said. "The 'why' behind that, I don't know."
All of this matters because authorities contend that Porter made a deliberate turn toward the water where Craig, 85, drowned on April 22, 2004. The defense says speed is the culprit.
Two years earlier, on March 5, 2002, Craig was crippled when Porter's Toyota Tundra veered off Lake Road and slammed into a tree.
Craig enlisted Porter's help to build an agricultural museum in 1999, after he inherited more than $2 million from a brother. He made the Hickman Community Church his beneficiary and gave Porter, its pastor, power over his financial decisions.
The museum was never more than a plan on paper. Porter, 57, of La Grange, is suspected of embezzling $1.1 million from Craig, then staging the wrecks to cover his tracks. He has been held without bail since his arrest Nov. 27, 2006.
The trial that began May 12 is heading toward a conclusion, with the defense resting its case earlier in the day after Porter's daughter Monica Tanner and niece Andrea Avila showed the jury photos of antiques Craig wanted to display in the museum, which are in a storage unit at Porter's home.
Defense attorney Kirk McAllister never called Porter's wife, Vicki, though she had been excluded from the courtroom throughout the trial because she was a potential witness.
Doug Porter offered an explanation about the fatal wreck shortly after Craig drowned, and again last week when he testified in his own defense.
Hours after Craig died, Porter told investigators from the California Highway Patrol that he was driving 30 to 35 mph when the truck was jolted because it hit a rock, then another, then landed in the canal.
Last week, Porter told the jury that he was driving too fast when he hit the rocks. He recalled putting his arm out to keep Craig from falling forward as they headed toward the water. He did not recall turning left.
"I was going faster than I should have been going," Porter said.
Varat said he used a process called photogrammetry to recreate the tire tracks along the embankment, which he used to determine the truck's likely speed. He said he saw no signs of braking in the 100 feet between the rocks and the left turn toward the water.
"It's a hard turn to the left," Varat said.
Bee staff writer Susan Herendeen can be reached at email@example.com or 578-2338.