On April 29, 2013, counsel for the plaintiffs issued a letter to Richard Cheney informing him of the lawsuits and asking him to refer the matter to counsel.
Counsel has requested a response by May 22, 2013.
http://witnessiraq.com/wp-content/uploads/2013/04/04.29.2013.Correspondence.Comar_.Cheney.SIGNED.pdf