Violated the number one rule in gun safety. The majority gun violence in the US is by people intentionally using the firearm to cause harm. No gun safety class is going to matter when gangs are shooting each other.

This is the case of an outspoken critic of the organization that promotes gun safety violating almost every single simple gun safety rule imaginable.

#1 Treat every firearm as if it's loaded
#2 Never point a firearm at something you do not intend to destroy
#3 Keep your finger off the trigger until you are ready to shoot
#4 Always be sure of your target and what's behind it
#5 Never freaking cock a single-action firearm until you are ready to shoot.

#5 I added in there. If you're not familiar with single action revolvers, you can pull the trigger to your hearts desire and the gun won't shoot if the hammer is not MANUALLY cocked.

That means Baldwin INTENTIONALLY cocked a loaded firearm without clearing the line of fire, without verifying it was unloaded, and then had his finger on the trigger. There is not accidentally pulling a trigger. You either have your finger away from the trigger or you're pulling it. Modern firearms often have an indention or other rest for your trigger finger to make it that much easier to keep your finger off the trigger.

Literally reading a simple boy scout firearms safety poster would have prevented this.