>Right are a completely arbitrary construction of organized society so it's strange to suggest there are any absolute rules that govern 'rights.'
Are you familiar with the United States Declaration of Independence [0]?
>We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.
It seems to me that 'rights' could exist without an 'organized society'. But, so far, I don't think any 'organized societies' really recognize 'rights of a dead person' (chiefly, I think, because there is no longer a 'person' to have rights).
Do you know of a law that grants rights to dead persons?