A quick analysis of the currently known facts of the "Batman Massacre" revealing similarities to past staged shootings, wherein funding planning equipment etc. was provided to the "perpetrator" via the FBI, CIA, etc.. The purpose for these staged events in the past has been to mold public opinion and to prepare the population for abandonment/ theft of rights and privacy.
The fact that the US Government has used manipulation techniques is well known and admitted. You can find this out by searching MKULTRA and "Project Artichoke" (the subsequent coverup).