Matt Fiddles claims that Jackson had been at "war" with his former bandmates and brothers for years.
He added that Jackson's paranoia and heavy drug use had got to the point where he wanted his brother Randy dead.
"Michael was caught in a war with his brothers for years," Fiddles told The Sun.
"They were desperate to sign him up to a $500 million (£309 million) deal for a Jackson Five reunion tour. By 2005, Michael had surrounded himself with Nation of Islam bodyguards and became paranoid to the point that he would bar family from coming into his home."
He added: "Things reached a head when Randy was trying to force his way past the bodyguards to speak to him in one of his rented homes. Michael ordered him to be shot dead.
"He was out of mind on drugs and luckily Randy was okay."
Matt Fiddles had previously made the claim that Michael Jackson had a secret sexual relationship with the late Whitney Houston.
Michael Jackson's estate recently signed a "huge" deal with Pepsi for future merchandise and commercials.