Michael Jackson (White House Photo Office)

“He’s lying. He’s guilty. Nobody was there but him,” Jackson’s mother, Katherine Jackson, said at a press conference following Dr. Conrad Murray’s arraignment on Monday. “He’s just trying to save his own behind… He killed him.”

Dr. Conrad Murray, who served as Michael Jackson’s personal physician before his death, faces up to four years in prison if convicted on the charge of involuntary manslaughter in the singer’s death. He was released after arraignment on $75,000 bail.

Both sister La Toya Jackson and father Joe Jackson have stated they think Dr. Conrad Murray wasn’t the only guilty party involved in Michael Jackson’s death, although the entire family believes he was the primary hand behind the singer’s demise and should have faced heftier charges. Joe Jackson, in particular, has hinted repeatedly that some of the blame should fall on those pushing Michael Jackson to commit to a grueling schedule for the ‘This Is It’ tour.

“There’s other people, I think, involved with this whole thing,” Joe Jackson said on CNN’s Larry King Live. “He was afraid to even do all of these shows [in his planned tour], because he was afraid that he wouldn’t get a chance to finish all of the shows,” Joe Jackson said. “He couldn’t do all those shows back-to-back. Even his kids say that he had told them that he would be murdered.”

Dr. Conrad Murray (YouTube screenshot)

Michael was murdered, and although he died at the hands of Dr. Conrad Murray, I believe Dr. Murray was a part of a much larger plan,” La Toya Jackson said in a press statement. “There are other individuals involved, and I will not rest and I will continue to fight until all of the proper individuals are brought forth and justice is served.”

>> Previously:  Michael Jackson Children Moving Tribute to Father at 2010 Grammy Awards