The deadly accident occurred on Sunday over Memorial Day weekend in Waupaca, Wisconsin, (population 6,069) located a couple hours straight north of Madison.

Casperson's premature death came during a "reunion party" with friends, during which the 44-year-old Illinois resident and his pals "decided to entertain themselves by setting off explosives," as Waupaca County Attorney Veronica Isherwood explained to a local TV station.

(Note: Originally characterized as a "pipe bomb," the device in question was later called a "cannon" by one of its constructors, so we're going with that.)

Keep your Darwin Awards jokes to yourself. Casperson's death seems like a real loss. How often do you hear a prosecutor leveling charges against someone say this about the parties involved: "These are all people that don’t have criminal records, all have strong ties in community, we don’t believe there was anything intentional about this."

That's how Isherwood characterized this, which makes us sad.

But it doesn't make what they were up to legal. Scott Mattes, Kenneth Niemer, and Robert Mattes have been charged with "homicide by negligent handling of dangerous weapons, explosives, or fire," a felony that could come with a prison sentence of up to 10 years. They've appeared once in court, and two of them have a second date set for June 11.

The major element of the cannon was a steel pipe, which Niemer had "manipulated with a plug welded onto the bottom" before bringing it to the reunion, per the criminal complaint.

At one point, after a failed firing of this amateur cannon, a can of WD-40 was dropped down the pipe, which stood four feet tall and a half-inch thick. Here's how Niemer describes the fatal blow:

"We dumped shotgun powder in the tube. We lit it once and it just flared up. We did it again but this time we used some paper toweling and put it in the pipe with a stick. We all stood by the fence. [Casperson] was standing by the side of the camper. When it went off, he landed on the ground.”

Let's assume that version's true, as Niemer probably knows as well as anyone that Casperson's wife was filming at the time. Attempts to revive him didn't work, and an autopsy found a "piece of steel" embedded in his abdomen.

Isherwood warned about the dangers of doing anything like this, pointing out that professionally made and legal-in-a-state-like-Wisconsin fireworks are "dangerous enough."