They found that the beloved actor and comic legend passed from asphyxia due to hanging in the manner of suicide.
An extensive toxicology evaluation revealed an absence of both alcohol and illicit drugs in Williams' system at the time of death.
Prescription medications, however, were detected in "therapeutic concentrations."
Shortly after this tragic passing, Williams' wife, Susan Schneider, spoke out about her late husband's struggles with addiction and depression.
"Robin spent so much of his life helping others. Whether he was entertaining millions on stage, film or television, our troops on the frontlines, or comforting a sick child — Robin wanted us to laugh and to feel less afraid," she shared in a statement.
"Since his passing, all of us who loved Robin have found some solace in the tremendous outpouring of affection and admiration for him from the millions of people whose lives he touched. His greatest legacy, besides his three children, is the joy and happiness he offered to others, particularly to those fighting personal battles."
Schneider also chose to address one of the major obstacles that the Oscar winner was facing in private.
"Robin's sobriety was intact and he was brave as he struggled with his own battles of depression, anxiety as well as early stages of Parkinson's Disease, which he was not yet ready to share publicly. It is our hope in the wake of Robin's tragic passing, that others will find the strength to seek the care and support they need to treat whatever battles they are facing so they may feel less afraid."
Williams is survived by his wife and three children from previous marriages: Zak Williams, 31, Zelda Williams, 25, and Cody Williams, 22.
If you or someone you know needs help, please call the National Suicide Prevention Lifeline at 1-800-273-TALK (8255).