It makes a good movie plot: the beneficiary of a wealthy relative devising a well thought out murder sure to never be solved. Yet this isn't just the stuff fiction is made of.
In one recent case, a vacationing couple went scuba diving. Yet only the husband surfaced. He claimed his wife had panicked underwater and drowned, an explanation neither the woman's parents nor the authorities in the country where the incident happened believed. And the plot deepens: the woman was quite wealthy when she married her husband and named him as primary beneficiary, where he was due for a hefty inheritance. In the event he died before her, at the time of her death his two children were to inherit everything.
Yet due to the suspicious circumstances surrounding the death, the woman's parents sued in civil court. A jury found the man guilty of causing his wife's death, and awarded her parents $3.5 million in damages.
The parents later pursued establishing that the man was a "slayer" within the laws of the state in which they reside. After a probate judge reviewed the will, noting that the husband had since officially been labeled a slayer, the judge ordered that neither he nor his heirs would receive anything. Furthermore, the slayer-husband was ordered to return $152,568 he had wrongfully taken from the estate.
So why should the children be punished for the sins of the father? The state's Supreme Court determined the children, now adults, could not inherit because that inheritance would confer a benefit on their father. The children had sided with their father during his trial and it was thought they might opt to use money gained in the would-be inheritance to help their father pay legal fees or other legal expenses. It is also conceivable they might give a portion of the money to the man, resulting in him benefitting from killing his wife.
Source: Verdict, "Mama's in the Graveyard, Papa's in the Pen": Why the Children of a Slaying Spouse Cannot Inherit," Joanna Grossman, Lawrence Friedman, February 5, 2013