A very old gun. It smells fishy to me. Guns just don't go off when dropped, even with safetys off and fully cocked. If the trigger isn't pulled, there's always some sort of firing pin safety that prevents accidental discharge when dropped.
I have a friend who bought a new Kimber SIS
fancy pants pistol.
He was showing it to a friend in his kitchen when he accidentally dropped it.
The pistol landed on the muzzle on the Spanish tile floor, and discharged.
Luckily no one was hurt.
Besides being embarrassed, he was very angry as this model was supposed to have a firing pin block to prevent such an accidental discharge.
He returned it to Kimber and they found nothing wrong with it.
So even modern weapons can fire when dropped.
The SIS has been discontinued by Kimber.
(What a silly name for a pistol)