LOS ANGELES (AFP) - Michael Jackson may have died up to an hour before emergency paramedics even arrived, and his doctor then lied about the stars condition and the key drug that killed him, a court heard Friday. Conrad Murray was also described as looking like a deer in the headlights when a paramedic surprised him in Jacksons bedroom, collecting items shortly after the seemingly-dead star was loaded into an ambulance at his LA mansion. The doctor in charge of the emergency room at the UCLA Medical Center in Los Angeles recounted how she was ready to pronounce Jackson dead before he was even brought in, since efforts to resuscitate him had failed. When the paramedics arrived, the patient had no signs of life, was clinically dead... and the estimated time down was at least 40 minutes, said UCLA medic Richelle Cooper. I made a determination based on that... to pronounce the patient dead in the field. The senior medics testimony came at the end of the first week of Murrays manslaughter trial over the King of Pops death on June 25, 2009, from an overdose of the powerful sedative propofol. Murray could be jailed for up to four years over Jacksons death at his mansion in the plush Holmby Hills district of Los Angeles, where the star was rehearsing for a series of comeback shows in London.