Why prosecutors calling more Harvey Weinstein accusers comes with risks

What to expect from the Weinstein trial

Prosecutors involved in Harvey Weinstein's New York trial said they plan to call four additional accusers from uncharged cases to testify as witnesses. The trial is set to begin opening arguments on Wednesday.

Weinstein faces charges that include rape and sexual assault involving two women, more than two years after a slew of accusations against him helped launch the #Metoo movement. He denies all of the allegations.

Prosecutors' strategy with the additional witnesses has been used before in a similar high-profile trial — that of Bill Cosby. "There certainly is value in numbers," said CBS News Legal Analyst Rikki Klieman on "CBS This Morning."

In a case with two accusers charging misconduct, their cases alone may not be strong enough, Klieman said. "When there's no forensic evidence, no physical evidence, late reporting — these cases are old, going back 2006, 2013. So you get four others," she said.

Klieman said that prosecutors are looking to try and establish a pattern of predatory activity, "that he always intentionally wanted to harm women."

However, she adds that the strategy comes with risks. "'Beyond a reasonable doubt' is the burden of proof on the prosecution and it's about those two women," Klieman said.

She said the additional women could open the prosecutors to accusations from Weinstein's lawyers that "they know how weak their case is," and "that's why they had to call four others."

When asked about what the defense team calls "loving e-mails" from some accusers, Klieman said: "When you have emails with one of the witnesses saying they want to introduce Harvey to her mother, another one that says 'I have a new phone number, please take it,' after an alleged assault and really loving and fond emails that go on, sometimes for years, what that is saying to the jury is that these women were not sexually assaulted."

However, she presented a strategy for the prosecution to combat the argument — a strategy that could also come from the Cosby trial. She said that the prosecution "calls the same expert witness that testified in the Bill Cosby trial very effectively, a psychiatrist who is going to say in rape trauma syndrome, women will often continue a relationship."

The trial, beginning Wednesday, will be decided by a jury of seven men and five women.