The Cosby Show alum Malcolm-Jamal Warner's cause of death has officially been revealed. The Costa Rican Judicial Investigation Agency (OIJ) confirmed that Warner's autopsy was completed on Tuesday, July 22. Warner's cause of death was "asphyxia due to submersion." It was ruled accidental. On Monday, July 21, TMZ and People reported that Warner had died at age 54, citing accidental drowning as the cause of death.