Sometime soon after dawn on Saturday, Dec. 8, 1990, a married couple from Casper saw a truck they knew fly past them on a familiar weekend drive.

Both said during court testimony Friday that they were sure they saw large plastic bags billowing in the bed of the pickup, bags authorities believe may have contained the body of a murder suspect's wife.

The day the state rested its case in the first-degree murder trial of David Bush, prosecuting attorneys questioned more witnesses about subjects familiar to the jury after two weeks of testimony: that the pickup truck was seen in or around Kaycee, that a child was with the defendant on that drive and that the defendant responded strangely to police questioning in the days, weeks, months and years following his wife's disappearance.

The defense continued to challenge memories and remind the jury that David Bush voluntarily talked to police about the disappearance of his wife even after being read his Miranda Rights, and denied killing his wife as he has all along.

During opening statements March 5, Natrona County District Attorney Michael Blonigen told the jury that evidence would show beyond a reasonable doubt that David Bush killed his wife, Lynn Bush, either late Friday, Dec. 7, 1990, or in the early hours the next day, and buried her on Saturday in a remote Wyoming locale.

Her body has not been recovered in the more than 16 years since David Bush reported her missing Dec. 9, 1990, when he told a Casper police officer he found the pickup truck that day in the Buttrey's Grocery Store parking lot, located on East 12th and Beverly streets.

David Bush has told police multiple times that his wife took the truck to the grocery store Saturday afternoon and never returned.

Three witnesses who lived in Kaycee at the time said they saw the pickup in or near their small town that weekend. Another two from Casper have said they didn't see the truck in front of the Bushes' house at about 9 a.m. Saturday, or in the Buttrey's Grocery Store parking lot around midnight the same night.

In multiple police interviews and during opening statements, David Bush and his lawyers have denied that he was ever in Kaycee that weekend.

The morning of Dec. 8, on the way from Casper to work on their retirement home in Story, Paul and Caroline Martin noticed a truck zoom past them as they traveled north on I-25 near the Midwest cutoff.

It was the Ford F150 that Paul Martin, then a Casper College vehicle maintenance supervisor, knew David Bush drove.

"He was particular with his truck, which was good, because it was nice," Paul Martin said Friday, testifying via a video teleconference call.

Martin is receiving treatment in Colorado for congestive heart failure, and 7th District Court Judge David Park sided with the prosecution and allowed the Martins to testify from a Colorado courtroom.

In the 10th Circuit U.S. District Courthouse, the jury watched the Martins testify on a television before Park, attorneys from both sides and David Bush. The couple testified for an hour, and the trial resumed at the Natrona County Courthouse.

Paul Martin recognized the truck by its distinctive license plate - 1-BUSH.

That Saturday morning, he noticed a few more things about the Ford. The first was that it was traveling at an incredibly fast speed, even for the highway.

"I was doing 65, 75, and it passed me real quick," Martin said.

Though he said the truck windows were tinted, Martin said the morning sun illuminated the inside of the truck. As it passed, Martin said, he saw a driver and a "passenger alongside the driver with a small head."

Earlier testimony from two counselors indicated that they believed Misty Bush, the daughter of David and Lynn Bush, suffered post traumatic stress disorder because she witnessed parts of the death and burial of her mother.

When the defense calls witnesses next week, the first counselor who saw Misty Bush, now Misty Knievel, after her mom vanished is expected to testify that he saw no signs of PTSD in the girl. After the state rested its case, Park told the jury to "keep an open mind," because there was a lot more information to come in the last week of the trial.

On Friday, Paul Martin didn't say he saw signs that the bags in the truck bed contained a body, but he knew they weren't filled with leaves. He said he was concerned that they would blow out and hit his Buick Skylark, but they didn't.

"They were well weighted and as an end result they did not blow out," he said.

Defense attorney Vaughn Neubauer challenged the Martins' memories of events, and asked them if they told the police in 1990 that they saw three shadows in the truck, the middle one possibly being a dog.

Paul Martin denied ever saying that. Caroline Martin said she didn't remember. Though they spoke with police together in 1990, the two testified separately.

Neubauer asked Paul Martin if he told police then about the bags, and he said he couldn't remember, but believed that he had. Caroline Martin, asked the same question, said "I don't know."

Amy Smuts, a DNA expert from the University of North Texas, testified Friday in regards to a mitochondrial DNA test she and her lab performed on a hair found on a suitcase strap in a garbage. She said it likely belonged to a relative of Gayle Knievel, Lynn Bush's mother. Defense attorney Kerri Johnson asked if the hair could have come from another link in the mother's genetic chain - Lynn Bush's sister or her daughter - and Smuts said yes.

Still, new DNA evidence collected from blood found in the pickup, blood found on a pint bottle of Smirnoff vodka and the hair from the suitcase strap - all samples the prosecution believes came from Lynn Bush - helped lead to David Bush's arrest at a Rawlins truck stop on Aug. 4, 2006.

Special agent Matt Waldock of the Wyoming Department of Criminal Investigations interviewed David Bush for an hour and a half after the arrest. The transcript of the tape is 64 pages long.

Waldock testified Friday that they went through details of Bush's alibi from Dec. 7 and 8, familiar already to the jury through previous testimony. He, Lynn Bush and their daughter Misty went to a movie. Then they decided to go camping. He drove the truck towards Alcova Lake, and parked it on a hill. The couple drank a screwdriver, made from supplies purchased that night, and listened to music for an hour or so. The wind picked up, and they drove home.

The next morning, they woke up. He washed his truck, a usual Saturday event, played with Misty and took a nap with his 2-year-old daughter. Lynn Bush had gone to get milk in the afternoon, and he never saw her again.

Waldock said David Bush couldn't remember during the interview if he bought the vodka that night or before, and he didn't mention taking Misty to McDonald's or the barbershop on Saturday, two parts of his original 1990 statements to police. As many witnesses have said on the stand so far, David Bush said his memory was better then than now.

Waldock asked David Bush about the three affairs he had after his daughter was born.

"He said he was going through a cocky and arrogant stage," Waldock said.

David Bush was solemn and emotionless during the arrest, Waldock said. His demeanor changed, Waldock said, when new evidence was presented to him.

Waldock told him about the Smirnoff bottle, how it was found in the couple's home and how blood on it tested positive for Lynn Bush's DNA in recent testing. Waldock said David Bush leaned back, rolled his head, gave a "deer in headlights" look and took a labored, audible swallow.

"That's pretty hard to believe," David Bush said that night.

They talked about blood found in multiple locations in the truck. About witnesses seeing the truck in Kaycee. About Trudy Dooling, his girlfriend at the time of Lynn Bush's disappearance, telling police about their time together on Dec. 7, when she said David Bush talked about killing his wife.

He said he could understand the blood being in the truck - he said he suspected there was a struggle Saturday in the grocery store parking lot, Waldock testified. The other accusations he denied, Waldock said.

Three times during the interview, Waldock said David Bush denied killing his wife. The only witness to say David Bush specifically said he killed his wife was a prison inmate. But after his arrest, did David Bush concede something?

"You have to build evidence to point to me … and you're doing a good job," he said at one point, according to Waldock. "I see where that's going."

All the evidence points at you, Waldock told him at the end of the interview.

Waldock said Bush responded: "Why didn't they solve it before they let me go off and start another family? I don't care about it anymore. I wanted to start a new life."

Contact reporter Cory Matteson at (307) 266-0589 or cory.matteson@casperstartribune.net.