Clearing the Dance Floor

Sounds like this fellow has danced himself right into the dog house. FBI (foolishly bad intelligence) dancing.

They should only let him carry one bullet and require him to keep it in his pocket.

Obvious Question: Why was there one in the chamber? If he kept them all in the magazine, he would not of almost have a tragedy

And why touch the trigger?

If what I read is correct, the FBI agent's gun went off when he attempted to pick up the gun after it fell out of his (wherever?) when he executed (pun intended) a dance move. Thank goodness that the innocent victim is expected to survive and will hopefully make a full recovery.

I'm guessing that the agent may soon need to get new cards that read "FBI -- Formerly with the Bureau of Investigation".

Somebody wounded?

According to the article I read (please see @Isamorph's OP link), yes.