Motes died on February 9 of an apparent drug overdose.
A spokesperson from the Office of the Los Angeles County Department of Coroner said they had "confirmed that there were (suicide) notes" on site.
"All we're saying at this point was that there was a note found," the representative told Us magazine.
Motes was found dead in a bathtub on Sunday afternoon.
"There were prescription and nonprescription drugs found at the scene. The role the drugs may or may not have played is not yet known," Lieutenant Fred Corral of the LA Coroner's Office said.
"She's being examined today. The investigator at the scene listed at this point that he is going with suicide, and we are waiting for the doctor to finish the examination."
A spokesperson added Tuesday that the autopsy had been completed. Toxicology results are still pending.
Following Motes' untimely death, Julia Roberts cancelled multiple scheduled engagements, including the Academy Awards' Nominees Luncheon in Beverly Hills, and an appearance on Jimmy Kimmel's late-night show, Jimmy Kimmel Live.
In a statement on February 10, the family said they were "both shocked and devastated."