Jandji, no action lies for defamation of a dead person.
http://austlii.edu.au/media/MLWS%20Commentary/Defamation%20commenary%20-%20Kayser,%20P/134.htm
And remember, anyone who has the filing fee can sue someone, but winning is another matter.
i get the distinct impression from this link, you know much more about legal doings than most people, but these aren't united states references.