Many states have specific rules on what roadkill you can claim. One of those states has made it completely illegal to take home animals you find along the road.
Over the Mardi Gras weekend, "Saffron" the pet possum was confiscated from his owner by the Louisiana Department of Wildlife and Fisheries in the French Quarter.
Every state has strange laws still on the books, but Louisiana has some very interesting ones and if you're in Acadiana you don't have to go far to hear about some.