The slaughters in Las Vegas and Sutherland Springs demand explanation, in the face of the ineffable. An understanding of the shooters' motives could restore our trust in our mutually cooperative existence. In this short communication we provide post-hoc rationale of both Stephen Paddock (Las Vegas mass shooting) and Devin Kelley (Southerland Springs mass shooting) and hypothesize that these shooters had genetically induced "Reward Deficiency Syndrome" (RDS) and a hypodopaminergia trait/state. In this particular case we are in pursuit of trying to obtain postmortem samples of mass shooters for subsequent epigenetic and neurogenetic analyses. It is our contention that early genetic identification of RDS and its pathological behaviors including hyper - sexuality, violence, a love for guns, even in children, could be a giant step forward in potentially saving lives.