Comes from the form of words that the judge used to use when passing sentence whilst wearing a bit of black cloth on his head (aka a black cap) and matching gloves: "The sentence of this court is that you will be taken from here to the place from whence you came and there be kept in close confinement until [date of execution], and upon that day that you be taken to the place of execution and there hanged by the neck until you are dead. And may God have mercy upon your soul." Amen.
As this was devised in the 18th century it is a bit archaic, and nowadays tends to be reserved exclusively for executions of animate miscreants eg Hanged, Drawn and Quartered (although you occasionally do see that as Hung, Drawn and Quartered). So an effigy might be hung from a gallows, but the original would be hanged. Describing somebody as hung means something quite different.
· 10 months ago