Cal,

Even if they did slip a round in there, as gun users we should know how to handle the gun (i.e., never assume it is unloaded).

It's true we're all taught how to safely handle a gun.
But how many of us would have pulled the trigger??? Guilty right here. Probably about half of us are.

Personally, I don't hold the shooter one bit responcible.
Shop owner and the gun show are.

If he pulled the trigger without checking the chamber, he is responsible.

Decocker and/or safety could be inoperable negating the need to pull the trigger to effect discharge of the weapon.

I remember years ago when my dad wanted to trade his P94 9mm, for a Glock 17.

He brought the Ruger to the gun show, the dealer who was interested in buying it was inspecting the handgun. Wouldnt ya know, a cartrage popped out when he checked the slide. I never seen my dad more emberased in my life.

Like Fabs said "never assume its unloaded".

My favorite gunshop closed the first of the year. One of the things that impressed me so much was his attitude towards safety. When you asked to see a gun, he would take it down, work the action to check for a live round, and then hand it to you. I would then check it myself, as I always check a weapon myself, and look it over. Upon handing it back, he would again check it before putting it away. A person can not be to careful. The gun shows I've taken guns to in this area meet you at the door and inspect the guns to make sure they are unloaded and then put a plastic tie through the action if possible. This unfortunate incident is just another nail in the gun show coffin.