A prime example of the limits on testamentary freedom arises in situations where one spouse disinherits the other spouse in a will. In a world of unlimited testamentary freedom, a wealthy businessperson could disinherit his or her spouse and leave that person destitute and on public assistance for the rest of his or her life. To avoid this, states have created spousal elective share laws, giving the surviving spouse the right to a set percentage of the estate, no matter what the estate plan says. For obvious reasons, state legislatures have reasoned that "public policy" favors ensuring that surviving spouses (who are often elderly) are provided for.
Most people do not take issue with spousal elective share laws. However, let's discuss some more controversial will provisions. Imagine that you really dislike your son-in-law, and want to encourage your daughter to divorce him. You may have excellent reasons. However, is it advisable to put a provision in your will or trust stating that your daughter will be disinherited if she does not divorce him within a certain amount of time after your death?
Don't count on a will provision that actively encourages divorce being upheld in court -- many states consider anti-marriage provisions to be highly suspect, or automatically void against public policy. In Illinois, there has historically been a distinction between conditioning an inheritance on the completion of a divorce that is already in progress (possibly legal), and requiring a potential beneficiary to begin divorce proceedings that were not already happening (void against public policy). However, a provision that in any way encourages divorce is likely to spark expensive probate litigation after your death, and the state of the law in the future is never guaranteed.
Finally, let's turn to an issue the Illinois Supreme Court wrestled with in 2009: Will provisions that disinherit family members that marry outside the faith. In the case of In re Estate of Max Feinberg, the court dealt with a will clause that sought to disinherit any descendant that married outside the Jewish faith. A provision of this nature pits testamentary freedom against other rights, such as religious freedom and freedom to marry.
Ultimately, the Feinberg court did not invalidate the religious restriction (overturning a lower court decision), finding that testamentary freedom prevailed. But it limited its finding essentially to the facts of this case. In non-legalese, this means the court ruled a certain way in this specific case, but was careful to avoid making broad pronouncements about the state of the law regarding religious restrictions in general. I would not read too much into this one result.
As this article from the American College of Trust and Estate Counsel notes, the Feinberg litigation was so expensive for the family, that there was no longer enough money left in the estate for the religious restriction clause to even matter. Tread carefully when putting any type of restriction in your estate plan that comes close to violating public policy, or your estate may also end up in unproductive litigation.
Note: The information above is not legal advice and is not the basis of an attorney-client relationship. If you need assistance, you can hire an attorney to assist you with your individual legal needs.