As an estate planning lawyer in Florida, I'm often asked by clients if they can leave their estate to whomever they choose. For the most part, a person can leave his or her estate to whomever they choose but there are some exceptions.
Florida has certain laws which run contrary to the general rule. These laws essentially mean that if a person makes a devise (gift) in their Will or Trust that a certain asset or portion of their estate is to go to a beneficiary other than as the law requires, the law "trumps" the Will or Trust. A few examples can help.
A first example arises when a person owns a primary residence--known as their homestead--and has a spouse or minor children. If the owner attempts in their Will or Trust to devise the homestead to someone other than their spouse or minor children, the devise fails. By law, when a person owns a homestead and has a spouse and minor children, the house must be devised to them. If not, by law, the spouse receives a life estate in the homestead and the minor children receive the remainder. If there's only a spouse, the spouse receives the homestead outright. This means the house cannot be devised out from under a spouse or minor children.
A second example in Florida arises when a person is married and attempts to devise his or her assets to someone other than their spouse. In that case, the spouse has the right to make a "spousal elective share." If so elected, the spouse is entitled to recieve 30% of the deceased spouse's estate--regardless of what the Will or Trust provides. In other words, a person cannot "cut out" their spouse from their estate--at least not entirely.
Understanding these and other laws impacting the right to devise one's estate illustrates why you need an experienced estate attorney in order to do your estate planning. If you do not, you're liable to make a devise which later will not hold up.