Because he says the Anthonys knew Caylee was not alive when he first met with them about conducting the search. i.e Expending funds to search for a child that was already dead, where those funds could have be used to search for other missing children.
He has not said he will sue, I’m just guessing.
In addition, to win a civil case does not require “reasonable doubt?
Only a 51% chance.
No one but the biological father (whoever he is) has the standing to sue her for wrongful death. The grandparents really don’t have standing. And if they did they can’t prove a great deal of damages.