There is no factual premise to form a basis for these conspiracy theories. The documentation regarding what happened at Jonestown is overwhelming.
See the following links:
The political machine of Jim Jones in San Francisco helped to elect politicians. It's no wonder they liked him, until the media began to reveal his darker side and victims.
Jim Jones was a drug user and apparently an addict.
The people who propose these conspiracy theories are often the same anti-government types that concocted stories about Waco. Even after congressional hearings, a civil trial and an independent investigation they also refuse to face the facts about that tragedy.
Both Waco and Jonestown were horrible cult tragedies and it denegrates the victims and nullifies history to view such events otherwise.
Tape recordings of Jones speaking in the end verify the group committed what he called "revolutionary suicide."
Likewise, both taped conversations and infrared photography have proven that Waco Davidians started the fire that claimed the lives of those cult members.
The government certainly made mistakes regarding both Jonestown and Waco. But this was largely the mistake of not responding earlier to avoid a potential tragedy.
The gross abuses that characterized both cult groups had been going on for some time before authorities took official notice.