The "Pirates of the Caribbean" star is suing his ex-wife for defamation after she penned an article for The Washington Post, claiming she was a victim of domestic abuse, while alluding to the allegations she made against Depp in their explosive 2016 divorce, when Heard claimed he had a history of violence, spurred on by his longrunning abuse of drugs and alcohol.
Depp has always denied the accusations, insisting she was the one who often attacked him.
Last month, Heard's lawyers had their request for access to Depp's "relevant" medical files approved by a Virginia judge, but they subsequently had to file an emergency motion seeking more documents relating to the 56 year old's mental health and prescription drug use after his representatives initially declined to authorise their release.
According to The Blast, the petition has since been approved, and Heard wants to use the information to suggest his alleged substance abuse issues, and the medications he used to treat them, contributed to his reported violent outbursts.
Heard's documents state: "(Depp's) mental conditions in combination with his rampant use of alcohol and drugs were inextricably intertwined with the abuse she suffered at his hands."
"Johnny's relationship with reality oscillates, depending upon his interaction with alcohol and drugs," the actress explained. "As Johnny's paranoia, delusions and aggression increased throughout our relationship so has my awareness of his continued substance abuse."
Depp maintains the violent outbursts never occurred, but Heard is convinced he simply doesn't remember, either due to his mental condition or because he was too intoxicated at the time.
The case continues.