Could I please see a legitimate legal cite on that? Note that this issue would only arise in very screwy marginal cases. I can cite many cases which have contained the common sense presumption that a person dies exactly once (e.g. it has been argued in many forms in many cases where a “murder” victim is taken off life support, especially if it was done at the patient’s own request as in the case of Georgette Smith in 1999) but I am not aware of anything that rises to the level of a insurmountable black letter legal principle
“The law recognizes” is a weaselly phrase that always raise immediate suspicions if it is not followed by a cite specifying the scope and force of the “recognition” claimed. Some have great weight (e.g. legislation; a SCOTUS ruling); some have virtually none (a court ruling that explicitly says “Cars don’t start themselves and run over bystanders” in one case may have no bearing on a separate product liability/wrongful death case that alleges that a car did exactly that)
According to your argument, the girlfriend would be open game for anyone to kill, not just the boyfriend. Similarly, by your argument, a person who fakes their death could be murdered by anyone, because, having once been ruled dead, they cannot die again. I can look up cases, if you really want, where the courts have convicted people for the murder of people who were already ruled dead. It’s not all that uncommon: people who commit life insurance fraud, or fake their deaths to illicitly escape other situations often have unsavory associations,
Would you say that a mob informant whose death was faked can legally be killed by the mob? (I don’t believe this is a general practice of the Wittness Protection Program, but they might choose not to blow the whistle on an informant who used “private initiative” to enhance his chances of survival)
Heck, by your argument, any death certificate I signed for a patient who was (for example) declared KIA in WWII would have equivocal status. I had a colleague who did exactly that about 10 years ago – and the courts gave his “impossible” declaration total weight over the earlier finding.
Even if your assertion were true, the law (and common sense) still says the girlfriend in the example was only murdered once. The first conviction was an error, and countless laws and fundamental legal principles state that a conviction can be in error. (I’d be happy to provide cites, if you genuinely deny that)
The “paradox” only exists in kindergarten logic: “but you said!”