What I meant was beyond that. You can't slander a dead person, for example. However it appears that this may not be as clear-cut as I had thought, for example if there is an Estate that is continuing to earn income from the assets of the deceased person, then there may be a basis for the Estate to sue for damages if a slander or libel reduces those earnings.
So, I (somewhat) stand corrected. At least in the case of someone like Tupac.