[zozbot234]

I don't think this is correct. People have been declared legally dead simply due to being missing for a long time, and there's nothing "permanent" or "irreversible" about being a missing person - sometimes they show up again.

[MereInterest]

There is a big difference between being dead and being declared dead. One is a fact about the universe, and the other is a fact about what somebody said about the universe. Seeing somebody who was dead and is now alive is cause to start a religion. Seeing somebody who was declared dead and is now alive is cause to doubt that initial declaration.