DENVER -- The man who operated the gun show where Eric Harris and Dylan Klebold obtained three guns they used in the Columbine shootings wants a judge to dismiss a lawsuit filed on behalf of a victim.

In a motion filed in U.S. District Court and made available Friday, J.D. Tanner claims a lawsuit filed by the family of wounded student Patrick Ireland should be dismissed because Tanner wasn't responsible for the injuries.

"Tanner states that he owed Patrick Ireland no duty and that any alleged negligence on his part could not, as a matter of law, have been a substantial factor in causing Ireland's injuries," the document said.

Ireland's family claims that Tanner bears some responsibility for his injuries. The lawsuit said that Tanner operated the show negligently and provided a place where guns could be sold to minors.

Ireland was shot in the head during the April 20, 1999, attack at Columbine. His dramatic rescue from a second-floor window was broadcast live on television.

His injuries left him partially paralyzed. He also suffers cognitive impairments and post-traumatic seizure disorder, according to his lawsuit.

Tanner has asked a federal judge to throw out similar lawsuits from the families of wounded students Sean Graves and Lance Kirklin.

The family of Richard Castaldo, also wounded in the attack, has filed a similar suit in federal court.

Harris and Klebold allegedly got three guns at Tanner's 1998 gun show with the help of Robyn Anderson, then 18. Neither Harris nor Klebold could legally buy guns at the time.

Harris and Klebold killed 13 people before committing suicide in their attack at Columbine High School.