I didn't know the real answer for this as well.... Apparantly it is legal to do so but the body has to be prepared and released to you from the funeral home. You must have paperwork on hand showing you are authorized to move the body.
GOOGLE had many entries on this subj and they all said about the same thing...
transporting bodies across the state lines
I know this was done alot in the old days by the various familys...
Would be a tough journey for me I'm sure...
What I didn't see was what happens if someone dies why you might be on a trip. I too would probably just start heading for the house no matter where I was located... This is most likely stretching the law since I would not have a death certificate issued...
Some official has to sign the death certificate I guess..
Roy Ken