COMPETING ALLEGATIONS:
The first is that of the police which is a claim based on their not yet completed investigation, that Rich was murdered in a "botched robbery" attempt. The parents, based on his support for Clinton and the struggle that left him bruised and his wristband damaged, also believe this is the most likely explanation.
The other allegations, all which come from the alt-right and Republicans:
1) Rich had access to DNC emails, which his parents say he did not 2)that the parents are covering up his involvement 3) that the police are part of the conspiracy to cover up the truth 4) that he leaked the emails to Wikileaks and 5) that he was murdered for the leaks. Further iterations also assume that the hospital is part of the cover-up and that someone at the hospital forcefully prevented them from treating him to prevent his death.
This explanation, once created by the alt-right, was most recently repeated, after 4chan unknown individuals made the claim that the hospital was forced to let him die, on the pages of the cutting edge progressive website,OPEDNEWS.com, adding a new claim, reported as fact, to the alt-right conspiracy theory, adding a new set of assumptions.
The narrative of the murder by Russians posing as FBI investigators (posing to whom is unclear) was made by a Republican lobbyist. He claims he has seen (but not revealed) evidence that the Russians murdered Rich.
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