More than three years after an Edgewood woman was killed by a piece of shrapnel from a homemade cannon, the man who fired the device pleaded guilty to involuntary manslaughter.

Max J. Fenton, 31, of Greeley, entered the plea in Iowa District Court for Delaware County, according to documents made available today. His trial in the case had been scheduled to start on Wednesday, Aug. 21, in Manchester.

If a plea deal is approved by a judge during a hearing on Oct. 29, the charge will be reduced from a felony to an aggravated misdemeanor and a pair of fireworks-related charges will be dropped.

The newly filed court documents do not include a recommended sentence. Under the deal, Fenton faces a maximum of two years in prison and a fine up to $6,250.

If the deal is accepted, Fenton also will be sentenced on Oct. 29.

According to court documents, Fenton illegally fired an “improvised cannon” made from the sawed-off barrel of a black powder rifle at his home on July 2, 2016. The breach on the cannon failed, and a piece of shrapnel struck 55-year-old Lori L. Heims in the head.

Fenton’s attorney, John Sullivan, previously argued that the cannon was not classified as a firework, undercutting the basis for the criminal charges. However, Iowa District Court Judge Michael Shubatt rejected a request to dismiss the charges.

While Fenton acknowledges that the evidence presented could result in a conviction, he disputed testimony alleging that he was indifferent to Heims’ condition, according to court documents. He also alleged that another person borrowed and repeatedly fired the cannon before July 2, 2016.

Fenton still potentially faces a trial in a civil suit connected to the case. Heims’ daughter, Amy Vermie, is suing Fenton for damages related to pain and suffering and for burial and funeral costs.

A trial in that case is set for Oct. 2 in Delaware County.