The true con artist

I've heard that criminals don't look like they are criminals. I experienced this first hand recently.
My boxer, Gideon rushed outside followed closely by his sister, Bella and they made an incredible noise. I figured I'd better check on them.. Somehow Gideon must have passed me on his way back and while I was looking for him outside he had toppled the tin with the reject biscuits in an had begun tucking in. Sneaky is not the word. What could I say - I'd been an idiot thinking anything edible was safe around Gideon!