The case was originally told by Don Harper Mills, then president of the American Academy of Forensic Sciences, in a speech at a banquet in 1987. After it began to circulate on the internet as a factual story and attained the status of urban legend, Mills stated that he made it up as an illustrative anecdote "to show how different legal consequences can follow each twist in a homicide inquiry". It is not clear when the date changed, but here is the story.

On March 23, 1994, the medical examiner viewed the body of Ronald Opus and concluded that he died from a shotgun wound to the head.

Mr. Opus had jumped from the top of a 10-story building intending to commit suicide. He left a note to that effect indicating his despondency.

As he fell past the ninth floor, a shotgun blast passed through a window, killing him instantly.

Neither the shooter nor the decedent was aware that a safety net had been installed just below the eighth floor level to protect some building workers. As a result, Ronald Opus would not have been able to complete his suicide the way he had planned.

“Ordinarily,” Dr Mills continued, “a person who sets out to commit suicide and ultimately succeeds even though the mechanism might not be what he intended” is still defined as committing suicide.

That Mr. Opus was shot on the way to what he believed was certain death nine stories below at street level, even though he probably would not have been successful because of the safety net, caused the medical examiner to feel that he had a homicide on his hands.

The room on the ninth floor from where the shotgun blast came was occupied by an elderly man and his wife. They were arguing vigorously, and he was threatening her with a shotgun. The man was so upset that when he pulled the trigger, he completely missed his wife, and the pellets went through the window striking Mr. Opus.

When one intends to kill Subject A but kills Subject B in the attempt, one is guilty of the murder of Subject B.

When confronted with the murder charge, the old man and his wife were both adamant. They both said they thought the shotgun was unloaded. The old man said it was his long-standing habit to threaten his wife with the unloaded shotgun. He had no intention of murdering her. Therefore, the killing of Mr. Opus appeared to be an accident; that is, the gun had been accidentally loaded.

The continuing investigation turned up a witness who saw the old couple’s son loading the shotgun about six weeks prior to the fatal accident. It transpired that the old lady had cut off her son’s financial support, and the son, knowing the propensity of his father to use the shotgun threateningly, loaded the gun with the expectation that his father would shoot his mother.

The case hence became one of murder on the part of the son for the death of Ronald Opus
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Now comes the exquisite twist.

Further investigation revealed that the son was in fact Ronald Opus. He had become increasingly despondent over the failure of his attempt to engineer his mother’s murder. This led him to jump off the ten-story building on March 23rd, only to be killed by the shotgun blast passing through the ninth story window.

The son had actually murdered himself, so the medical examiner closed the case as a suicide...