Oooops...

[Lamplighter]

If this was the only time such a thing happened it would be surprising.
But it's not...

The Independent
Heather Saul
8/14/13

US gun-safety instructor shoots a student during demonstration

A gun instructor in Ohio accidentally shot a student whilst
leading a class for people seeking permits to legally hold a concealed firearm.

73-year-old Terry Dunlap was demonstrating with a 38 calibre pistol
when it went off and shot Michael Piemonte, 26.
He and his wife were attending the all day class on how to carry guns
for their own safety, he reportedly told local media.
<snip>
The police have ruled the shooting an accident and Mr Dunlap has not been charged.