Bars to Inheritance: Homicide, Abuse, or Abandonment
There is a strong public policy that anyone who kills, abuses, or abandons a donor, should not profit from such wrongdoing by allowing the wrongdoer to inherit the property of the donor, either through intestacy, will, or nonprobate instruments, such as life insurance.
A person convicted of an intentional and felonious killing cannot inherit from his victim, which is based on the obvious equitable principle that a killer should not profit from his crime. Hence, a killer may not receive any property transfer from his victim, whether by intestacy, will, or nonprobate instruments, such as life insurance. However, a killer who already had an interest in the property before the killing can still receive the property.
The killing must be willful and felonious. Hence, anyone convicted for involuntary manslaughter, or was adjudged insane at the time of the act can still inherit from his victim. Self-defense is also not a bar to inheritance.
Although there is much debate about it, mercy killings and assisted suicides are intentional and felonious, and the killer is generally barred from inheriting from the victim.
Long ago, there were many states that didn't have so-called slayer statutes that specifically prevented a killer from inheriting from his victim, and, consequently, some courts have ruled that the killer should receive the property because to do otherwise would be legislating from the bench. Nonetheless, most courts have ruled, even in the absence of a specific statute, that equity requires that the killer should not profit from his crime. (Indeed, this would create a perverted incentive for relatives to kill those who are better off!)
When there was no specific statute barring a killer from inheriting from his victim, the courts have followed the letter of the law by allowing the title of the property to pass to the killer, but in the form of a constructive trust for the next in line to inherit.
Most states and UPC §2-803 now have slayer statutes that specifically prevent a killer from inheriting from his victim, and generally treat the killer as if he predeceased his victim.
In most jurisdictions, if the killer has issue or descendants, then the killer's issue will inherit; however, a few jurisdictions, such as California, Rhode Island, and Virginia, have statutes that bar even the killer's issue to inherit.
A criminal conviction is res judicata (a judgment that can be used as an established fact in another proceeding involving the same issue) for a civil proceeding but an acquittal is not determinative, since a criminal conviction requires proof beyond reasonable doubt, while a civil proceeding only requires a preponderance of the evidence.
Since only a preponderance of evidence of an intentional and felonious killing is required to bar the killer from receiving either an inheritance or nonprobate property, such as life insurance proceeds, at least one court has ruled that a conviction at the trial-court level satisfies the preponderance-of-the-evidence standard even if the conviction is being appealed. This court decided that after Scott Peterson's conviction of the first-degree murder of his wife, Laci Peterson, and his unborn son, that, although the appeal of the murder conviction was still pending, California's Probate Code §254(b) only required a preponderance of the evidence of intentional and felonious killing. The court concluded that the murder conviction proved by the preponderance of the evidence that the killing was intentional and felonious. The burden of proof then fell on Scott Peterson to refute it, but he failed to do so. Hence, he was barred from receiving the proceeds of the $250,000 life insurance policy on his wife's life. (Principal Life Insurance Company v. Peterson - Murder Conviction Sufficient To Bar Award Of Life Insurance Proceeds Despite Pending Appeal)
Abandonment or Abuse
Many jurisdictions add abandonment and abuse as bars to inheritance, especially the abandonment of children by their parents, a spouse abandoned by the other spouse, and elder abuse, which can include physical, emotional, or fiduciary abuse or neglect of a dependent adult. Under these jurisdictions, the abuser cannot inherit from the abused.
The Chinese have greatly expanded the notion that worthy heirs should inherit at the expense of the unworthy ones, even if the worthy heirs are not relatives, but, nonetheless, provided support for the decedent. However, this system is very expensive to administer, since the courts would have to determine everyone who was worthy and who was not. This system is probably a bonanza for the Chinese lawyers.