I recently investigated a "shots fired" call at a residence in my jurisdiction. In this case, the elderly gentleman had an older (1932 I think) Colt .32 semi-auto pistol that he had carried for years (he is a local merchant and has a permit). He claimed to have removed the gun, in its "inside the pants holster" and laid it on his kitchen table, where it suddenly just discharged hitting his kitchen wall. No injuries, just a shook up citizen. I took the weapon to our alleged state firearms "expert" where he examined the gun and declared the citizen a liar and told me that I should press charges. My Chief and I agreed that it was most unlikely that this particular citizen would do anything so stupid, so, the Chief and I did a little test at our range. I repeated the claims of the citizen, and lo and behold, after about a minute of just sitting on the shooting bench, the damn thing just went off. I took it to a local gunsmith, who, after carefully examining the action determined that there was a notch worn on the striker and when laid down at a certain angle (such as when still in the holster with the belt clip down), gravity pulled the retainer into the notch and caused a discharge. (He went into great detail, about worn parts etc.) When I told the state "expert" about it he literally laughed in my face and declared that the gunsmith was a liar too! Needless to say, the citizen was more than slightly unnerved about his "carry" weapon discharging of its own volition. The Chief and I have lost all faith in our alleged expert, and the citizen has since retired the little pocket piece to his collection and now carries a nice little Taurus Millinium PT-145 in .45ACP.
Just remember, KAKA DOES occur!
Semper Fi
An excellent object lesson about maintaining firearms in good working order, especially with older guns that don't have the kind of redundant safeties that modern handguns usually have.