Once in awhile you'll come across someone that wants to disinherit their spouse. Sometimes it isn't done with ill-will. For example, maybe it is a second marriage situation and both spouses decide they don't need to leave anything for the survivor. Sometimes it is ill will.
The general rule is that you can only disinherit your spouse if he or she agrees to it. In other words, a surviving spouse can choose (elect) after your death to basically ignore your will or trust that doesn't provide for that surviving spouse, and have basically a third of your estate go to them. For example, if you left your entire estate to your children and not your spouse, your spouse can say "wait a second. I don't like that idea. I'll take one-third of the estate thank you very much." And believe it or not, money can make people change their minds.
For a while, individuals were using trusts to get around this "election against the will", but eventually the Iowa laws corrected that "end around" planning. But now, a recent ruling out of an Iowa district court in Pottawattamie County created another option. In a December 2009 ruling, the district court permitted some bank accounts with a payable on death (POD)/ Transferrable on Death (TOD) designation to escape the spouse's ability to get the one-third elective share. The result, under this ruling, is that you can now disinherit your spouse by using the POD/TOD designation on these accounts. While this ruling is not the law of the state, the court creates a roadmap for a valid argument to properly disinherit your spouse.
TOD and POD accounts are very easy and flexible planning tools. In fact, they can be almost too easy. If this ruling continues to stand, it may result in some unintended consequences contrary to the intent of the spousal election laws. The court places the burden on the Iowa legislature to correct the statute if they don't want this type of "loophole". Time will tell.