The Los Angeles County coroner's office was assisted in the inquest by psychiatrists Norman Farberow, Robert Litman, and Norman Tabachnik from the Los Angeles Suicide Prevention Center, who interviewed Monroe's doctors and psychiatrists on her mental state.[30][31] Based on the advanced state of rigor mortis at the time her body was discovered, it was estimated that she had died between 8:30 and 10:30 p.m. on August 4.[32] The toxicological analysis concluded that the cause of death was acute barbiturate poisoning; she had 8 mg% (mg/dl) of chloral hydrate and 4.5 mg% of pentobarbital (Nembutal) in her blood and a further 13 mg% of pentobarbital in her liver.[30] The police found empty bottles of these medicines next to her bed.[30] There were no signs of external wounds or bruises on the body.[33]