Appeal filed in rural Ottawa manslaughter case

Shannon believes judge was wrong not to throw out his charge

The Iowa man charged in a rural Ottawa killing is asking an appeals court not to send him back to trial but instead throw out his charge.

Mason Shannon, 46, of Newton, Iowa, was scheduled for a hearing Thursday on his pending charge of involuntary manslaughter, a Class 3 felony carrying 2-5 years in prison. He allegedly placed Ottawa resident Michael Castelli in a neck restraint, which proved fatal, during a struggle outside the Bonnie Plants growing facility.

Shannon was convicted at a bench trial but that verdict was thrown out over a judicial error. He and his lawyers have since tried to persuade Visiting Judge William Dickenson to throw out the case. At a February hearing, Dickenson refused.

A hearing on fresh post-trial motions was scheduled Thursday, but that was called off after Shannon’s lawyers decided to instead appeal Dickenson’s ruling.

Records on file at the Third District Appellate Court in Ottawa show Shannon has lodged an appeal; but a briefing schedule has not yet been issued. It could be weeks or months before Shannon spells out why Dickenson was wrong in refusing to dismiss his charge.

Shannon’s lawyers previously argued making Shannon stand trial again would be double jeopardy; the U.S. Constitution prohibits someone being tried twice for the same crime. Dickenson disagreed, ruling double jeopardy didn’t apply in Shannon’s case.

Tom Collins

Tom Collins covers criminal justice in La Salle County.