Johnny Depp’s memory of his “disgraceful conduct” towards Amber Heard is “so severely impaired by drug use” that he may not have been aware of the extent of his “violence and terrifying behaviour”, the High Court has heard.

Lawyers for The Sun newspaper said there is a “wealth of evidence” to support Ms Heard’s allegations of domestic violence by Mr Depp, which paints a picture of the actor as “a hopeless addict who repeatedly lost his self-control and all ability to restrain his anger”.

Mr Depp, 57, is suing the tabloid’s publisher, News Group Newspapers (NGN) and its executive editor, Dan Wootton, over a 2018 article which labelled him a “wife beater”.

The Pirates Of The Caribbean actor denies the allegations of violence made against him by Ms Heard, 34.

On Monday, the case – the biggest English libel trial of the 21st century – entered its closing stages as NGN’s legal team began making closing submissions.

Sasha Wass QC, for NGN, told Mr Justice Nicol that evidence of Mr Depp’s “drug and alcohol-fuelled lifestyle provides a backdrop to the events in question”.

She said: “Firstly, it demonstrates that the claimant was subject to irrational mood swings and abnormal behavioural patterns, which would not have been present when Mr Depp was clean and sober, and Mr Depp has a name for this metamorphosed entity, namely ‘The Monster’.

“The other aspect which is important in terms of substance abuse is Mr Depp’s recollection of his own disgraceful conduct, which is so severely impaired by drug misuse that he may not even have been aware of the extent of his violence and terrifying behaviour which, on more than one of these pleaded incidents, put Ms Heard in fear of her life.”

Ms Wass also told the court: “The days are long past when the courts in this country required corroboration before accepting the unsupported testimony of a female complainant.”

She later said it is “trite” to suggest that a person who chooses to remain with a violent partner “cannot be a victim”.

She said: “We submit… that the testimony of a complainant of domestic violence is sufficient to prove the case, provided that the complainant – Ms Heard in this case – gives credible and reliable evidence.”

However, she said that in this case, unusually, there is also a “wealth of evidence” to support Ms Heard’s account.

She said there were text messages and emails to support her evidence, as well as medical evidence from those who were treating Mr Depp for his addictions.

Ms Wass said: “This paints a picture of a hopeless addict who repeatedly lost his self control and all ability to restrain his anger.”

At the outset of Monday’s hearing, Ms Wass said that the defence to the article complained about by Mr Depp is “one of truth, namely that Mr Depp did indeed beat his wife”.

She said: “For the defence of truth to be substantiated, the defendants need to prove on a balance of probabilities that Mr Depp assaulted Ms Heard on at least one occasion.

“During the last two weeks, the defendants have established that many more than one incident of wife-beating took place over the course of the relationship between the claimant (Mr Depp) and Amber Heard.”

The three-week trial at the Royal Courts of Justice in London has heard evidence from both Mr Depp and Ms Heard, as well as other witnesses.

Mr Depp was asked about 14 allegations of domestic violence which NGN rely on in their defence against Mr Depp’s claim – all of which the actor denies – as well as his past relationships with women including Vanessa Paradis, Winona Ryder and Kate Moss, and his well-documented use of drink and drugs.

He accused Ms Heard of “building a dossier very early on” in their relationship to align herself with the #MeToo movement.

And he told the court no other woman had ever accused him of hitting them.

In her evidence, Ms Heard claimed her ex-husband threatened to kill her “many times, especially later in our relationship”, and would blame his actions on a “self-created third party” he called “The Monster” – who she said she was “terrified of”.

In a witness statement, Ms Heard accused Mr Depp of verbal and physical abuse, including screaming, swearing, punching, slapping, kicking, headbutting and choking her, as well as “extremely controlling and intimidating behaviour”.

She also said Mr Depp was “extremely jealous” and accused her of having affairs with stars including Leonardo DiCaprio, whom he nicknamed “pumpkin-head” after Ms Heard auditioned with him.

Mr Depp is suing NGN and Mr Wootton over an April 27 2018 article with the headline: “Gone Potty: How can JK Rowling be ‘genuinely happy’ casting wife beater Johnny Depp in the new Fantastic Beasts film?”

His lawyers say the article bore the meaning there was “overwhelming evidence” Mr Depp assaulted Ms Heard on a number of occasions and left her “in fear for her life”.

NGN is defending the article as true, and says Mr Depp was “controlling and verbally and physically abusive towards Ms Heard, particularly when he was under the influence of alcohol and/or drugs”.

Mr Justice Nicol has said that his judgment will be reserved.