They can lie under oath, but the evidence against them is clear -- and the evidence that could be brought out would drop them to their knees.  Perjury charges would be a God-send compared to the death sentence or life imprisonment some would get.  Would the Dems  risk that?  If the Clinton, Obama, CIA, Bush, Biden, Romney massive criminal evidence came out, and the bottom fell out of the Dems coup (Comey Clan), I doubt RBG issue would get the Dems hoped for public backing.