News: Who or what killed BRITTANY?

Girl, Interrupted (1999)

Nearly over 4years of Brittany Murphy's passing, her father, Angelo Bertolotti is still questioning what caused the Clueless star's death. He has always been dissatisfied with the coroner's ruling that his daughter died from pneumonia and anemia at the age of 32. So, after finally securing samples of the actress' hair, blood and tissue, Bertolotti submitted them for independent testing, and the results seem to suggest possible poisoning.
The question now is WHO poisoned Brittany?