DENVER (CN) - An economist testified Wednesday that an expert witness for plaintiffs in the Colorado gun-control trial "deliberately ignored" some data and used only instances that would not "contradict his assertion."
Wednesday was day eight in the federal bench trial presided over by USDC Chief Judge, Marcia Krieger.
Thirty-one plaintiffs claim that three state gun laws signed into law in 2013 are unconstitutional. They include a ban on magazines bigger than 15 rounds, regulations on private transfers and the introduction of universal background checks.
Defense attorney Matthew Grove called University of Colorado at Boulder Professor Jeffrey Zax to the witness stand early Wednesday morning. Zax is an economist and referees for thesis presentations in social sciences.
Zax said he believes the ban on high-capacity magazines will reduce the risk to civilians and would reduce the carnage from mass shootings.
"Large capacity magazines are a mass murderer's weapon of choice. If we deny them their weapon of choice, they will be less effective to achieve their goals," Zax said.
Grove asked Zax what he thought about plaintiffs' witness, Gary Kleck, and his testimony on his studies in gun violence and firearm regulations in the first week of the trial.
Zax said he watched Kleck's testimony and believed Kleck's findings were incorrect.
"Are there any problems with Kleck's studies?" Grove asked.
"Well, there are many," Zax responded.
Zax told the court that Kleck's studies were biased.
"He had deliberately ignored several [shooting] instances. He ignored instances that would contradict his assertion," Zax said.
Zax had another problem with Kleck's testimony. Kleck said he found high-capacity magazines beneficial because they could help a person defend himself from "multiple assailants."
Zax disagreed, saying data show that a person who fires a gun for self-defense does not use more than 15 rounds.
"Apart from mass shootings, the objective is never to exhaust a magazine. No one expects people to go into a situation to exhaust their magazine," Zax said.
During cross-examination, an attorney for the plaintiff asked Zax about his expertise on firearms.
Zax made it clear he has no expertise on the mechanics of a firearm nor does he have knowledge on how fast parts on a firearm can wear out. Zax said he has not read the rules and regulations that govern gun possession in Colorado.
The defense is expected to rest today.
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