The case against defendants charged after a 10-year-old boy was decapitated at a Kansas water park should be dismissed because the Kansas attorney general's office abused the grand jury system and presented flimsy evidence to obtain criminal indictments, defense attorneys argued Friday.

During a hearing in Wyandotte County court, attorneys for Jeff Henry, Tyler Miles, John Schooley and Schlitterbahn corporate entities said grand jurors heard improper evidence that unfairly prejudiced jurors against their clients, The Kansas City Star reported .

The grand jury found that the defendants were responsible for the death of Caleb Schwab at the Schlitterbahn Waterpark in Kansas City, Kansas, in August of 2016. The boy was killed when his raft went airborne and hit a metal pole on the Verruckt water slide, which was billed as the largest in the world when it opened.

Defense attorneys argued Friday that the grand jury should not have been shown clips from a Travel Channel television show that chronicled the construction of the 17-story water slide, which was scripted and filmed for dramatic effect.

"They decide, strategically, to play to the grand jurors fictionalized, dramatized television as truth for grand jurors to rely upon to make the determination to provide an (indictment)," said Jeff Morris, an attorney representing Schlitterbahn general contracting affiliate Henry & Sons Construction.

Adam Zentner, assistant Kansas attorney general, argued that defense attorneys were suggesting grand jurors were "too stupid to discern a television show from evidence. We take exception to that characterization. This jury was aware and intelligent."

Affiliates of Schlitterbahn and other companies that developed the water slide settled with Schwab's family for nearly $20 million before criminal charges were filed.

The Kansas attorney general took over the case from the Wyandotte County District Attorney and convened a grand jury, rather than the usual procedure in criminal cases of holding a preliminary hearing that allows defendants and their lawyers to review evidence before a judge, who then decides whether enough evidence exists to bring a criminal case.

The defense attorneys also objected to the grand jury hearing about a lifeguard being crushed to death in 2013 at a Schlitterbahn water park in South Padre Island, Texas. Miles' attorney, Tricia Bath, argued defense attorneys would have objected to testimony about an unrelated case three years before Schwab's death.

Zentner defended his handling of the case and said he believed the state's evidence would have been allowed at a trial.

"This case comes down to the victims that were hurt and the methods that were used," Zentner said.

Miles is charged with involuntary manslaughter, aggravated child endangerment and aggravated battery. Henry, Schlitterbahn's owner, and Schooley, Verruckt designer, and Henry & Sons Constructions are each charged with second-degree murder, aggravated battery and aggravated endangerment of a child. Prosecutors contend the defendants designed and operated a ride that they knew was dangerous.

Two maintenance workers at the park were acquitted of impeding an investigation. The water slide has been torn down. Schlitterbahn officials declined this month to say whether the park would open this year.

Wyandotte County Judge Robert Burns is expected to hold a later hearing to announce his decision.

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