Good one!

The dog should be arrested for hiding evidence, in this case the weapon.

One of my former employees was an ambicious woodworker. While using his table saw he managed to cut off an index finger and part of another one. He called to his wife who immediately called the EMS (she was a cop and of course got a quick response). They wrapped his hand and when the EMS arrived they suggested that they take the severed finger along to the hospital for possible reattachment. After digging through a pile of saw dust the finger was not to be found. About then the dog comes back into the shop with mud on his feet and begins sniffing around the floor.

They concluded that he was looking for another finger to take out and bury.