British victims of sexual offences could be deterred from reporting abuse after the aggressive cross-examination of Harvey Weinstein’s victims, legal experts have warned.

The Hollywood mogul’s trial had to be halted at one point when his lead lawyer, Donna Rotunno, reduced one of the two main accusers to uncontrollable sobbing after more than four hours of grilling.

The witness, who alleged she was raped twice by Weinstein in 2013, also appeared to have a panic attack after Rotunno’s questioning, during which the lawyer painted the witness as a serial liar who manipulated Weinstein in order to advance a career in the film industry.

James Mulholland QC, vice-chair of the Criminal Bar Association, said : “The successful prosecution of Weinstein could backfire on the basis of a misunderstanding as to how cases are conducted in the UK.

“It could be a case of ‘one step forward, two steps back’ in that the successful outcome of the Weinstein case could encourage women to come forward but then ultimately deter them because they think court experiences are the same in every English-speaking court.”

Mulholland, of 23 Essex Street Chambers, said that UK courts have undergone a “massive sea change” in their treatment of vulnerable witnesses over the last 20 years, adding: “There’s no way witnesses would be subject to anything even close to the same treatment in the UK.”

Despite the changes, rape charges, prosecutions and convictions in England and Wales have fallen to their lowest level in more than a decade while the number of rapes recorded by police more than doubled over six years to 58,657 in 2018.

A 195-page study by HM Crown Prosecution Service Inspectorate last year also criticised prosecutors for making intrusive and unnecessary demands for complainants’ mobile phones and medical records.

But Laura Hoyano, a barrister and academic, said US courts have a lot to learn from the UK when it comes to sexual offences cases.

“I’m very keen that complainants are not deterred from coming forward on misunderstandings from the Weinstein case,” she said. “It’s very important for British women to understand that no rape trial across the UK would proceed in the same way as in any state in the US.”

The US constitution enshrines the right of the accused to face their accuser. In contrast, courts across the UK offer vulnerable witnesses a range of special measures, including independent sexual violence advisers, a live link in court and the use of a screen between them and the accused.

“The US constitution is often interpreted as requiring face-to-face confrontation,” said Hoyano. “They also require adult complainants to testify in chief, which means their lawyer questions them in court, while we use police interviews.”

Kate Ellis, a solicitor at the Centre for Women’s Justice, which last year launched a legal challenge against the CPS over its failure to pursue rape cases amid allegations of a covert change in policy on how it handles the crime, said she was also concerned about the impact of Weinstein’s guilty verdict.

“I worry that the successful prosecution will lead to platitudes that we in the UK have learnt that women will be believed if they come forward,” she said.

“But the problem is that unless our culture changes, so that prosecutors are rewarded for bringing credible cases forward regardless of whether they result in a guilty verdict or not, we’ll continue to be far too risk-adverse in the UK about which cases go to court or not.”