TMZ has learned Gary Coleman divorced Shannon Price nearly two years ago ... raising issues about her authority to make final medical decisions on Gary's behalf.
Gary's divorce lawyer, Randy Kester, tells TMZ the couple divorced on August 12, 2008, and as far as he knows they never remarried.
Kester does not know if Price had a power of attorney to make medical decisions.
A hospital official tells TMZ they have "become aware he may not have been married to her." But the official said she was portraying herself as Gary's wife and they didn't require further proof.
The official did not say if Shannon had a power of attorney.