What's the (legal, environmental etc etc) difference between a (cooked) chicken carcass (left over from Sunday lunch) and an (also very dead) bird, although maybe uncooked in your wheelie bin?
I always find that one of my hens keels over the day after the binmen have been... but holes in the ground have to be very deep, as badgers (and foxes) can smell quite well and try to dig any kind of carcass out... Seen it... large stone on top also helps.
Btw what are you supposed to do with your fallen hens?