Careful How You Carry

From September 3, 2014 Reuters:

(Reuters) - An Idaho State University assistant professor with a concealed-carry gun permit shot himself in the foot with a semiautomatic handgun that accidentally discharged from inside his pocket in a chemistry classroom full of students, police said on Wednesday.

There is no detail explaining  uow this nappened.  But my guess is that the trigger guard was not enclosed by a holster, and either a finger, wallet or key got inside the trigger guard. Always have a pocket pistol in one's pocket the  trihhrthuardtol in a pocket holster that covers the trigger guard.