One of Harvey Weinstein's accusers was told by police to delete any files from her phone that she wanted to keep private, prosecutors have admitted.
Oct 18: Assistant District Attorney Joan Illuzzi-Orbon said the complainant was told by a detective to "delete anything she did not want anyone to see".
Mr Weinstein's lawyer said the development "undermines" the case.
The Hollywood producer faces charges involving alleged sex assaults on two women. Mr Weinstein denies the charges.
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"My office had asked Complainant 2 to produce any and all cell phones that she might have used during the time she interacted with the defendant," Ms Illuzzi-Orbon wrote in a letter to Mr Weinstein's lawyer, Ben Brafman.
She adds, however, that the woman said she was then advised to remove files "before providing the phones to our office".
Despite this advice, the woman still provided the phones used to communicate with Mr Weinstein "without any deletions", Ms Illuzzi-Orbon said.
Mr Brafman later released a statement in response to the letter, saying the news "further undermines the integrity of an already deeply flawed indictment of Mr Weinstein".
He earlier requested that the entire case be dismissed.
Last week a charge against Mr Weinstein by actress Lucia Evans was dismissed by a judge in New York after she was said to have given a differing account of events.
Mr Weinstein has been accused of sexual misconduct by more than 70 women.
The accusations against him helped awaken the #MeToo movement, which has seen hundreds of women accusing high-profile men in business, government and entertainment of sexual abuse and harassment.
Mr Weinstein has agreed to wear a GPS tracker and to surrender his passport.
He also faces additional investigations in Los Angeles and London, and by the US federal government.
The 66-year-old, who has been on $1m (£750,000) bail since his arrest in May, denies having non-consensual sex, his lawyers have previously said.