Transcript for Actress Rosie Perez testifies in Harvey Weinstein trial in support of key witness
I'm so proud of her that she did it. And she did it in such a way, dignified, calm, clear. Reporter: Firebrand attorney Gloria Allred, fresh from the courtroom and the media frenzy surrounding the trial of disgraced movie mogul Harvey Weinstein. Sitting down to reflect on the epic events unfolding in front of her eyes. Her client, Annabella sciorra, became the first woman ever to accuse Weinstein of rape in a criminal court. Courage she's shown she knew it would have to come out in a court of law. It could never be maintained as private. She was still willing to do it. Reporter: Ski yore ar says Weinstein raped her more than 25 years ago. What happened on that night? She was at dinner. There were a number of people there. Mr. Weinstein offered to drop her off at her home. She accepted. She went upstairs and got ready for bed, got into her nightgown, was preparing to go to bed, and suddenly there was a knock on the door. Reporter: It was Weinstein. Sciorra says he forced his way into her Manhattan apartment and pushed her into the bedroom. He took her arms and locked them over her head, and so therefore she couldn't do anything. Reporter: Sciorra said on the stand she was punching him, kicking him, just trying to get him away from me. He was much larger than she was. Overpowered her. And he did overpower her. Reporter: Sciorra, who became emotional at times, said Weinstein raped her. He then forcibly performed oral sex on her, telling her "This is for you." She is giving an account of Harvey Weinstein raping her. It was emotional, and it was powerful. And the question's going to be do the jurors believe it? Reporter: The actress testified that weeks later she ran into Weinstein at a restaurant and confronted him. She claims he threatened her, saying "This remains between you and I "His eyes were black. I thought he was going to hit me right there." The 59-year-old is most famous for her emmy-nominated role -- Hey. Reporter: -- As Tony soprano's mistress on "The sopranos." You have good taste. Reporter: She was an up-and-coming actress in Hollywood in the early '90s, starring in movies like "The hand that rocks the cradle." How did you come to be a nanny? Reporter: When she says the rape took place. Sciorra says at the time she confided in her friend and fellow actress Rosie Perez. She told her she'd been raped, only revealing months later it was Weinstein who did it. Perez took the stand today, testifying that a distraught sciorra was crying. Perez says she encouraged her friend to go to the police but sciorra refused saying, "I can't. He's going to destroy me." The details that Rosie Perez provide are entirely consistent with the details that Annabella offered on the witness stand. Rosie was a very powerful witness today. She stood her ground. She did not let the defense undercut what she had said. She repeated it several times, what she says that Annabella told her. Reporter: The defense team told ABC news in a statement, "The only opinions that matter are the jurors'. Ms. Allred's job is the easiest. She watches other people try cases." Weinstein's defense team pressed Perez on why she didn't tell authorities about her friend's alleged rape. Sciorra never report it either. There are many reasons that many women never report it. Some blame themselves for what happened. Wrongfully blame themselves. If I went to the police, would they believe me? Would they do anything? They may fear loss of professional opportunities. Who will believe them? Against a rich powerful famous man. Reporter: The defense team tried to undermine sciorra's credibility, claiming she showed up intoxicated to the set of the 1993 movie "The night we never met," which she denies. I keep trying to tell him that it's like he just doesn't want to listen. Annabella sciorra. Reporter: The defense also questioned her honesty to a 1997 appearance on David Letterman in which sciorra says -- I have a bad reputation. I was caught recently in the last couple years lying about quite a few things. What do you make of that? It was supposed to be a dramatic courtroom moment. That's a late-night comedy show with David Letterman. Nobody's under oath. It's just a bunch of jokes. This is not a joke. Reporter: One area the defense team tried to exploit, sciorra's uncertainty about the exact date the alleged rape took place. Tonight Weinstein's defense added in a statement to ABC news, "It's more convenient that way. No way for Mr. Weinstein to potentially show he was elsewhere." You have to judge the honesty of the witness. Can you trust this witness's credibility or not? I think she came across extremely well. Reporter: My colleague Amy robach sat down with Weinstein's attorney Donna ratuno in November. Annabella has told so many different stories. Her first line of conversation about this was that absolutely nothing ever happened with Harvey and then it evolved and the story kept changing. She says the chances of charging Weinstein publicly would change her life permanently and she wasn't prepared to face that because of all the scrutiny. There was real intimidation going on. Well, but did they feel intimidated or were they more concerned about what could potentially happen to them and were they willing to play a game that they then decided they weren't willing to play? Reporter: Sciorra told the court the alleged rape led to her drinking heavily and harming herself by cutting. Sometimes she recalled she would slice her hands and fingers and paint a white wall on her apartment blood red. I wish I had known her then. And it just makes me admire her even more now, the courage that she's known. It just breaks my heart to see what she was going through in those days and over the years. Reporter: Weinstein has denied all the allegations, saying any sexual relations were consensual. The 67-year-old is on trial for five felony charges, which include rape and sexual assault. But sciorra's alleged rape is not one of them. Because it's past the stachtd of limitations. But prosecutors hope her testimony will demonstrate Weinstein's alleged pattern of predatory behavior. More than 80 women have accused the disgraced movie mogul of sexual misconduct. Many of them say he intimidated them into silence. Newly released audio from journalist Ronan farrow's "Catch and kill" podcast seemingly shows Weinstein threatening model amber Gutierrez's career after she rejected his advances. If you don't trust me, then we have no reason to do anything and you will lose big opportunits. Reporter: This trial is a watershed moment for many in the me too movement including some of Weinstein's accusers like rose Mcgowan. The trial means so much to so many, but it will mean the most to the brave women testifying and to all of us silence breakers. Reporter: But it focuses on the allegations of only two women. An unidentified woman who alleges Weinstein raped her in a hotel room in 2013 and Mimi halei who says Weinstein forced himself on her in 2006 when she was working as a production assistant. Women have the right to say no, and that was a no, regardless of the circumstances. It was very embarrassing. It was very humiliating. But she will testify to that. And more. Reporter: Haleyi is also represented by Allred, who spent her career fighting for women's rights. Allred has become a tireless force in the "Me too" movement, representing dozens of women against men like Jeffrey Epstein, Bill Cosby, and R. Kelly. They're starting to prosecute these famous men. This is a seismic legal shift. It is. I give all credit to the women. That really to me is what the "Me too" movement is all about. It's about the empowerment of women. I am going to take that rage about what he has done to me and the fact that I've had to live with this secret for many years, I'm going to turn it into positive action. Reporter: Allred is con vinced that regardless of the verdict in the Weinstein case the "Me too" movement is a moment of reckoning. It's not just the reckoning in the culture. It's the legal reckoning. It's about justice now. It's not just about truth telling. It's about the culture saying okay, we are going to work to make persons who are alleged to be predators accountable to their victims. And of course that trial continuing next week.
This transcript has been automatically generated and may not be 100% accurate.