Actually there is a rule saying. : prisoners found i n a location they should not be can be killed.
One sec I'll check the rule
EDIT:
15: GUARDS may kill any PRISONERS that are found in locations they should not be at.
also as soon as the round starts if ts are out of their cell they are not KOS , you must give an order.
Also on free day they can state guns are Kos and kill you, but that has also happened to me when I was killed in vent on free day Grom
One sec I'll check the rule
EDIT:
15: GUARDS may kill any PRISONERS that are found in locations they should not be at.
also as soon as the round starts if ts are out of their cell they are not KOS , you must give an order.
Also on free day they can state guns are Kos and kill you, but that has also happened to me when I was killed in vent on free day Grom