Mason Shannon acquitted in rural Ottawa death

Mason Shannon was acquitted of involuntary manslaughter Thursday as a judge handed down a not-guilty verdict in the 2017 death of Michael Castelli of Ottawa.

In a 45-minute ruling, visiting Judge William Dickenson made quick work of how Castelli died during a struggle at the Bonnie Plants growing facility in rural Ottawa.

Although two pathologists debated whether Castelli died from asphyxia or an enlarged heart, Dickenson said he was more persuaded by evidence that Castelli died from asphyxia resulting from a chokehold.

“The simplest explanation is generally the correct one,” the judge said, adding later, “There’s no doubt in my mind the defendant put Mr. Castelli into a chokehold.”

It is clear to me that (Shannon) had a right to defend himself and a right to defend others.”

—  Judge William Dickenson

But Dickenson said he wrestled with the “much more complicated” question of whether Shannon acted recklessly and without lawful justification.

Ultimately, the judge said, the state could not meet its burden of proof.

“It is clear to me that (Shannon) had a right to defend himself and a right to defend others,” Dickenson said. “I believe, ultimately, this was not an intentional killing – [there’s] no doubt in my mind.”

Shannon showed no reaction as the verdict was read, although his eyes appeared reddened as he glanced back at the spectator gallery.

He declined to comment after the verdict.

Castelli’s mother was present for the verdict and, accompanied by family, exited the courtroom and out of sight, possibly into a secure corridor. Family members said they were unsure whether she wanted to be approached for comment.

Shannon, 49, of Newton, Iowa, stood for a February bench trial, his second, in La Salle County Circuit Court. Although found guilty at his first trial, he and his lawyers successfully argued for do-over proceedings after a judicial conflict arose during round one.

That there was a struggle in 2017 and that Castelli needed to be restrained was not disputed at trial. Toxicology results showed that Castelli was under the influence of alcohol, cannabis and hallucinogenic mushrooms, and witness testimonies depicted a man out of control.

Three men at one point were trying to restrain him at the Bonnie Plants facility.

Prosecutors had alleged that Shannon overdid it when he placed Castelli into what had been variously described as a headlock, chokehold or carotid sleeper hold that lasted for several minutes. One witness estimated that the hold lasted about 10 minutes.

But the agreements ended with how Castelli died.

Dr. Valerie Arangelovich, a board-certified forensic pathologist, testified that she conducted an autopsy and spotted a series of burst blood vessels that indicate asphyxia. She also found some hemorrhages in Castelli’s neck that were consistent with a chokehold.

Witnesses also testified that Castelli was unresponsive when released from Shannon’s grip. Prosecutors allege that Shannon overdid it and, thus, was guilty of recklessly, if not intentionally, killing Castelli.

Shannon and his lawyers countered with a pathologist who rendered an entirely different conclusion.

Dr. James Filkins testified that he reviewed Arangelovich’s report as well as witness statements not available at the time of the autopsy.

Filkins testified that the burst blood vessels could have resulted from CPR, not necessarily from asphyxia, and the neck injuries could have resulted from the struggle itself rather than from a chokehold.

Filkins didn’t think the hold was sustained long enough to induce death.

Castelli also had an enlarged heart and a thickened wall in a heart chamber. Arangelovich said an enlarged heart is not uncommon among athletes and active individuals such as Castelli, an avid cyclist and basketball player.

“I do not see any reason why his heart would contribute to his cause of death,” she testified.

Dickenson said Thursday that he agreed with Arangelovich, calling Filkins’ conclusion “a reach.”

“I did not find him to be particularly persuasive,” the judge said, adding later, “He just really ignored a lot of the larger scientific findings in this case, in my opinion.”

Determining recklessness proved more challenging. Dickenson said he parsed the witness statements in hopes of determining whether there came a point where Castelli was subdued and the chokehold had to stop.

The judge said he found no case law to give him guidance – “I searched mightily for something directly on point” – and, ultimately, was unable to identify a point at which Shannon’s conduct tipped into territory that was clearly reckless.