Natasha Lyonne

Natasha Lyonne is the first to admit she hasn't always been a saint.

The actress, best known for films such as American Pie, But I'm a Cheerleader and Slums of Beverly Hills, is also well-known for her personal struggles behind the camera, including her DUI in 2001 and a 2006 stint at a drug and alcohol treatment center. Lyonne says she's been able to use those latter experiences while playing a patient at a mental institution in Law & Order: SVU."I have a very specific, sort of public past when I was maybe more of a troublemaker. You end up in places with girls who are similar to the character I play," Lyonne tells TVGuide.com.

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In this week's episode (10/9c on NBC0, Lyonne plays a woman who was seen being sexually assaulted but — after years of falsely crying rape — denies anything happened. The role of Gia Eskas was written specifically for Lyonne and the actress says it's clear why. "I've actually met a lot of girls like Gia. I feel privileged that they wrote this episode for me where I felt like I'm able to draw from some of the incredible survivors that I've met in my life and try to tell their story in an honest way," she says. "For me, there's a personal stake in letting young girls know that it's OK to be honest about their life story without it being a shameful thing. It's very important to me."

Although the subject matter is serious, Lyonne also says she was drawn to the role because of the dark humor employed by Gia throughout the ordeal. "A lot of these girls are determined to live and to enjoy themselves and to make jokes. There's a great deal of humor involved. I thought that was the most appealing aspect of this character," she says. "Coping through comedy is such a healing tool in general and you really see that a lot in these recovery communities."

Watch full episodes of Law & Order: SVU

Humor is not just one of Gia's strongest tools, it's also of Lyonne's. When asked about her prior knowledge of SVU, the actress, who recently guest-starred on New Girl and will be seen in next year's American Reunion, said that she has not only seen every single episode of every edition of Law & Order -- including the short-lived Trial by Jury — but has grand plans for her own spin-off. "A whole separate spin-off that I would really enjoy being on would be if they did one with Bebe Neuwirth, Criminal Intent's Vincent D'Onofrio, SVU's Richard Belzer and Ice-T, and then I could come on recurring as Gia Eskas," she deadpans. "That would be a dream show."

Watch a behind-the-scenes look at Lyonne's SVU episode here: