The key here on why they get away with it, from the GatewayPundit, "When Ty Clevenger requested documents from the FBI related to any investigation into the death of Seth Rich, they replied that they never investigated Seth Rich and they don’t have any records on him."  – "But when documents were requested from the NSA, they replied that they won’t release their records regarding Seth Rich because it’s a matter of national security." In other words a coverup.