As it is in most states you must first attempt to get premmision from the land owner. If turned down then contact the Game Wardens.
Had this problem a couple times while living in AL.
In both cases the land owner said I couldn’t retrieve the downed deer and to stay off their property. After contacting the Game Warden, he came out and instructed the land owner to either retrieve the deer himself and process it or allow me to do so. If not he was going to issue a ticket for Wanting Waste (hopefully I spelled that right).
In one case the land owner took the deer. The other allowed me to get it.
Both land owners stated they had no idea they were breaking the law by not allowing for retrieval or taking care of the game themselves.