A defense witness testified Monday that a windshield fracture pattern is consistent with Todd Kendhammer’s account of a crash he said killed his wife last year.

But a second defense expert told jurors he doesn’t believe a pipe fell from an oncoming truck and went through the glass.

The defense opened its case Monday in La Crosse County Circuit Court in the second week of Kendhammer’s first-degree intentional homicide trial in the death of his wife, Barb.

Kendhammer will testify Tuesday as the third witness in the defense case.

The 47-year-old told West Salem man told authorities that he saw a 53-inch, 10-pound galvanized steel pipe roll from an oncoming flatbed truck about 8 a.m. Sept. 16, 2016, while the couple were driving to Holmen on Hwy. M in the town of Hamilton. Barb Kendhammer died the next day. Prosecutors contend her husband caused the fatal injuries and drove the pipe through the window to disguise the cause of her death.

The windshield fractured initially when Kendhammer punched the windshield under the rear-view mirror with his left hand trying to deflect the airborne pipe, said Mark Meshulam, an expert witness who specializes in glass and windows.

Next, the pipe punctured the windshield. Then the glass fractured again when Kendhammer pried the pipe downward as he removed it while standing outside the car, he testified.

A butterfly-shaped fracture pattern, Meshulam said, indicates the last fracture wasn’t an impact but rather was created by pressure.

A State Crime Laboratory analyst testified last week that an object struck the exterior of the glass before the pipe broke through because multiple cracks run through a 1½-inch diameter piece of glass broken out by the pipe in front of the passenger seat.

But Meshulam testified that thick crack running through that circular piece of glass was caused by Kendhammer punching the windshield.

Meshulam told jurors he formed his conclusion after inspecting how the cracks converged and reviewing photographs of the scene, the transcript of Kendhammer’s interrogation by police, and reports from the crime lab and Wisconsin State Patrol.

The crime lab analyst had access only to a short statement from Kendhammer when forming his opinion.

The analyst also said the windshield was broken when the passenger seat was empty because of the volume and spread of glass particles on the passenger seat. The number of particles, Meshulam told jurors, “looks about right.”

On cross-examination, Meshulam said the pipe cut into the windshield at an angle from the passenger side.

“And that is consistent with someone standing next to the car and taking a pipe and punching it through a windshield, correct?” District Attorney Tim Gruenke asked.

“Well, um, whoever wanted to do that could angle the pipe at whichever angle they wanted,” Meshulam said.

To account for the injuries to the base and middle knuckles on his left hand, Kendhammer would have had to punch the windshield with his wrist bent backward slightly, Meshulam said.

In his report for the defense, Meshulam wrote “adrenaline-fueled super-human strength” is necessary to shatter the windshield with a punch and that Kendhammer “rose to the challenge that few people could or would have.”

“That sounds rather subjective, doesn’t it?” Gruenke asked.

“Um, because I’ve been in the glass business for so long, it’s hard to tell if that’s objective or subjective,” Meshulam said.

According to Kendhammer, after the pipe pierced the windshield, he drove about 100 yards north and another 100 yards east on Bergum Coulee Road, where the couple’s Toyota Camry slid into reverse and rolled backward into a grass ditch.

A passerby saw the Camry half in the ditch, the passenger side door open and its windshield intact on the drizzly and overcast morning.

The sun could have been in his eyes because “overcast doesn’t mean every single inch of the sky is covered by clouds,” Meshulam said.

When pressed by Gruenke, Meshulam told jurors he earned $240 per hour to work on the case and $350 per hour to testify. He disagreed that he is an advocate for Kendhammer, but added, “I always want to do a good job for my clients.”

Barb Kendhammer died of injuries inflicted by the pipe after it came through the windshield, said Barry Bates, a biomechanics expert for the defense. He formed his conclusion by focusing on three bone-deep cuts to the back of her head, broken nose and spinal injury, although Barb sustained a total of 50 injuries.

After spotting the airborne pipe, Bates said, Barb ducked and turned her body to the right to avoid the object, causing it to strike the back of her head and “skipping” through the scalp to leave the cuts on the back of her head.

She likely broke her nose on the dashboard and suffered whiplash, he said.

Bates disagreed with the findings of a forensic pathologist who performed Barb’s autopsy, who testified she did not suffer any injury consistent with a pipe coming through the windshield. The pathologist, Bates said, was viewing the injuries from a medical standpoint, not a biomechanical one.

It would be difficult to explain the three deep cuts to the back of Barb’s head if they were inflicted while she was not in the car, Bates testified.

“I could come up with some wild theories,” he said.

On cross-examination, Gruenke asked Bates whether he calculated foot-pound force when analyzing Kendhammer’s version of the crash.

“First of all, I don’t think (the pipe) came off a truck and through the windshield,” Bates said.

“Well, I don’t either,” Gruenke replied.

It’s “reasonable to assume” the pipe struck Barb, causing two deep diagonal cuts to the center of the back of her scalp, then skipped and caused another deep diagonal cut to the left of the first cuts, said Bates, who told jurors he has earned $14,000 working on the case.

A bruise on Barb’s jaw is consistent with a punch and marks on her neck are consistent with her scratching to remove someone’s hands from her neck, Bates testified. It’s also possible Barb’s nose was fractured by a punch to the face or by having her head slammed into the dashboard, he said.

Bates said that Todd Kendhammer’s version of the crash meant the pipe would have had to travel 20 mph horizontally for 35 hundredths of a second. In that third of a second, Barb Kendhammer would also have had to see the pipe and moved to protect herself.

Gruenke pressed Bates on whether a person could jam a pipe through a windshield.

“I’ve seen a person try to penetrate a windshield on the first try and not succeed,” he said.

“Like in this case,” Gruenke said. “No further questions.”