The prosecution is asking a jury to find Mostrong guilty of vehicular manslaughter, hit and run and driving under the influence.
Defense attorney Robert Espinosa on Monday called Plourd to the stand to recreate the crash that led to Michelle's death in an effort to show there was little Mostrong, 21, of El Centro, could have done to avoid the crash.
Plourd said during testimony the golf cart was stopped on Wheeler Road facing south in the northern section of the road in the way of any oncoming traffic.
Plourd further testified that, based on his investigation, it appeared Mostrong's van hit a motorcycle alongside the cart, pushing the motorcycle into the van.
Plourd said the van then struck Michelle, who was thrown 107 feet from the point of collision.
Plourd also testified that the scene was altered before the California Highway Patrol arrived. He said drag marks at the scene and a fluid spill mark on the road indicate the motorcycle was moved after the crash.
There was no information about who would have altered the scene.
Under questioning from Espinosa, Plourd said the headlights on the golf cart were off at the time of the crash.
As proof, Plourd pointed to filaments — a coil-like device within the light bulbs. He said if the lights had been on, the crash would have caused the filaments to stretch or uncoil to some degree. However, he said the filaments appeared unaffected by the crash, a sign, he said, the lights were off at the time.
Plourd also said Mostrong was likely driving close to 40 mph when the crash occurred. He reached that conclusion based on the distance Michelle was thrown.
Plourd told the jury he did two traffic surveys on Wheeler, which, he said, showed the average speed of traffic on that road is about 48 mph, faster than Mostrong was traveling, Plourd claimed.
Espinosa asked if Mostrong acted in any way other than a "prudent individual would act?"
Plourd responded, "Mr. Mostrong was acting in a reasonable and prudent manner."
Espinosa then showed a video of a test done on Wheeler in which the same van involved in the crash was driven on Wheeler under similar conditions as Oct. 7. A similar golf cart to the one that was hit was stopped on the road for the test.
The video showed that it was difficult to see the cart until the van had nearly reached the cart. Espinosa used the van to show there is little Mostrong could have done to avoid the crash.
As Espinosa finished questioning Plourd, Robinson asked to postpone his cross examination of this witness because Robinson said he had not previously seen the video and did not know about some of Plourd's testimony before hearing it in court Monday.
Espinosa claimed Robinson was told about the things Plourd would be testifying about but did not pursue them. Robinson denied the statement.
The judge, saying that because some of Plourd's testimony was based on events that happened after the trial began, granted Robinson's request and scheduled his cross examination of Plourd for 9:30 this morning.
The prosecution has argued the lights of the golf cart were on at the time of the crash, stating that when the Highway Patrol arrived they did find the lights on.
The prosecution also has contended Mostrong was under the influence of both alcohol and marijuana when he got behind the wheel of his van.
Toxicologists have testified it is impossible to say whether Mostrong was under the influence.
Mostrong did leave the scene in the van and didn't turn himself into authorities until 17 hours after the crash. By that time, even if he was under the influence of alcohol at the time of the crash, the alcohol was out of his system.
While Mostrong did have marijuana in his system, he had used it four hours before he was tested, which means the blood test on Mostrong could not show whether he had marijuana in his system from the night of the crash.
The defense has argued Mostrong was not under the influence.
Staff Writer Darren Simon can be reached at 337-4082.