It is not disputed that Levi Aaron is mentally disturbed. He was treated and medicated long before his crime.
The sole question should be was he conscious of what he was doing. The actual crime shows a clear pattern of premeditation. As of the moment it does not appear Aaron sexually molested his victim. Given the massive search have he may not had the time or he was motivated by something else.
Unfortunately for the public the crime was committed in an area with a Cuomo flunky DA Charles Hynes who will not under any circumstances consider Capital Punishment. This undercuts a valuable starting point in any plea deal.