Eyewitnesses, including the victim's husband, testified Tuesday in the manslaughter trial of Todd Spangler, the Waterloo man operating a boat pulling an inner tube that struck a dock, killing Jennifer Dwyer last June.

Prosecutors say Spangler was driving recklessly and drunk at the time near 251st and Leavenworth in the West Shores neighborhood, which surrounds a lake, but his lawyer argues it was an accident, not a crime. Attorney James Martin Davis says his client wasn't driving recklessly and despite his blood-alcohol level being twice the legal limit, it wasn't a factor.

"The tube didn't hit the dock. What happened is when they were pulling G's in the whip, the girls skidded off the tube and skidded into the dock and it was a very, very unfortunate tragedy.”

Four witnesses say differently. Heidi Lichtenberg and Angela Bolamperti each testified they were in the boat. Lichtenberg says she and Spangler were talking about centrifugal force and both heard Spangler say "watch this" before turning the boat hard.

"That's what tubing is all about, that's not reckless, that's called creating G's in the whip,” says Davis.

Dr. Jeff Nielsen was on shore that day and testified that he saw the tube hit the dock. "I saw people explode into the dock and go flying past the dock."

John Dwyer, the victim's husband, also testified that he saw the tube hit the dock. However, Davis argued his testimony has changed.

"I think his recollection was faulty today because he had been interviewed early on at length by the sheriff's department about what happened, what he saw and at no time did he ever say he saw the tube hit the dock.”

Davis adds despite testimony to the contrary, the evidence will show otherwise. "You're going to see from the evidence as we later go on, there is absolutely no evidence whatsoever that tube hit the dock forensically.”

The trial continues Wednesday. Spangler and his wife, who was on the tube with the victim, are expected to take the stand.