Man charged with stabbing cop at Chiller Theatre expo deemed not guilty by reason of insanity

A Connecticut man accused of stabbing an off-duty police officer at a horror-themed event at a Parsippany hotel in 2022 was found not guilty by reason of insanity by a state Superior Court judge in Morris County, just over a week following a bench trial.

Judge Claudia Jones issued her written order June 28, finding David Knestrick's defense attorneys proved the 48-year-old was mentally ill, or suffered a disease of the mind, that rendered him unable to comprehend what he did was wrong when he stabbed an officer during the Chiller Theater Expo at the Hilton Hotel , causing the man critical injuries.

The affirmative defense does not mean Knestrick did not commit the offense or is innocent, with Jones noting in her decision that prosecutors had enough proof to show Knestrick committed the crimes in which he was indicted: aggravated assault, aggravated assault with a deadly weapon, possession of a weapon for an unlawful purpose and theft. It allows Knestrick to be released into the community, but requires he abide by various conditions, including psychiatric treatment.

A forensic psychology expert testifies

Dr. Gianni Pirelli, a forensic psychologist hired by defense attorneys, opined Knestrick was suffering with mental health issues prior and during the Oct. 30, 2022 stabbing that led to a "defect of reason to truly comprehend the wrongfulness of his actions." Knestrick's primary diagnosis is bipolar disorder with psychotic features, which was consistent with symptoms and behaviors Knestrick's providers had seen from him in the past, Pirelli testified during the trial.

Pirelli's decision was not from his own personal confidence; rather, his opinion stemmed from a combination of his own evaluations of Knestrick and data provided from numerous professional sources that showed significant preexisting issues and psychotic symptoms. In May 2022, five months prior to the expo stabbing, Knestrick displayed similar "grandiosity, racing thoughts and paranoia" during an encounter with family members that also involved a knife, Jones wrote in her decision.

Pirelli noted that Knestrick had regularly been using THC — the compound in pot that causes a high — but called it an "aggravating" factor in the incident, and not a causality.

"Marijuana with THC use aggravated what the underlying mental illness was and is at the time," Pirelli said.

A defendant's substance use "muddies the waters," making it difficult to determine if it is the cause of a change in a person's inhibitions and behaviors, Pirelli said. But he had the benefit of time with this case and was able to evaluate Knestrick when he was sober in the fall and winter of 2023, he said. Despite his sobriety, Knestrick had still exhibited mental health concerns that raised questions, including beliefs related to human trafficking and conspiracies.

Prosecutors countered during the roughly two-hour-long bench trial that it was unknown whether or not Knestrick was actually sober during Pirelli's evaluations in 2023. Pirelli noted he does not drug test his clients, but said Knestrick had not appeared under the influence at the time.

Knestrick presented with what appeared to be a "deterioration of his mental health" — as opposed to a sudden "snap" in behavior — the day of the stabbing, Pirelli said. Knestrick had believed the horror and sci-fi themed event was a prime setting for human traffickers to engage children and adults, his attorney noted during his November 2022 detention hearing.

Knestrick had grabbed the cellphone of a 12-year-old boy who was taking pictures after he believed the child was being victimized, defense attorney John Azzarello said. When the boy's father and several others approached, Knestrick told his attorney someone had grabbed his arm at the same time the security guard intervened, and believing everyone was involved in a "conspiracy," Knestrick responded by stabbing the officer.

'I want to see him rot': Victim speaks out

Robert Turkowsky, a Kearny police detective who retired in October 2023 after nearly 25 years and who was stabbed during the event, urged the judge to order Knestrick serve time in jail or in a mental health facility for "as long as you can do it."

Turkowsky's liver was lacerated and he was considered "critical" and at risk for several complications, Jones wrote in her decision. Turkowsky, who was working private security during the event, claimed Knestrick tried to attack him twice, and had he not fallen to the ground after the first stab, "other things could have happened."

He wasn't short on expressing his feelings, stating that he believed with Knestrick's mental health conditions, he should have not been left alone in public.

"He's a menace to society," he said, adding that he wanted to see Knestrick "rot in a cell."

The mother of the 12-year-old boy also spoke, stating that the incident will impact her son and her family's lives "forever."

"They talk about crossing the line," she said. "Where is the line drawn? Who's next? That's what I ask."

Prosecutors requested actions by the court to assure Knestrick did not violate conditions, such as drug screens and barring him from non-prescription drug and alcohol use, including marijuana, which Jones granted.

Knestrick will also be ordered to continue outpatient mental health treatment and will reappear for a final hearing in August before a judge. He must comply with treatment and medication monitoring requirements and not possess or have access to firearms, knives or any other weapons. He is barred from contact with the child and the officer, as well as their families.

Email: lcomstock@njherald.com ; Twitter: @LoriComstockNJH or on Facebook .

This article originally appeared on New Jersey Herald: Man charged with stabbing cop at Chiller Theatre expo deemed not guilty by reason of insanity