Based on Johns' autopsy results, medical staff at the Orange County Coroner's Office have deferred his cause of death pending toxicology results, TMZ reported.
Johns, who competed on the Fox reality singing competition's seventh season in 2008, passed away on Friday after reportedly spraining his ankle and seeing a doctor on Thursday.
Reports have been swirling for days that a blood clot could've contributed to his sudden death, however, police officials told TMZ that Johns had been drinking alcohol heavily around the time of his passing and might've been prescribed pain medications.
The toxicology tests will determine whether alcohol and/or drugs played a role in Johns' death.
Johns is survived by his wife Stacey Vuduris, whom he wed in 2007. The singer had finished his Idol stint in eighth place.