One added: "Her condition prevents doctors from performing any tests to determine if she was driving under the influence of alcohol."
Famed for her high-profile romance with Ellen DeGeneres in the 1990s, Heche has spoken openly about her previous battle with substance abuse.
She told ABC News in 2020: "I drank. I smoked. I did drugs. I had sex with people. I did anything I could to get the shame out of my life."
She added her hedonism was a result of her painful childhood that stemmed from being sexually abused by her father, Donald Heche.
Anne added: "I'm not crazy. But it's a crazy life. I was raised in a crazy family and it took 31 years to get the crazy out of me."