Many adolescent narrators in literary fiction ring so false to me. You can feel the authors are writing their idea of a teenager; they use formal, academic words the character would never know or use. It’s very difficult to capture a true teenage voice—to make your character sound authentic, but not make her sound like an idiot. The challenge of creating this language intrigued me. How does an intelligent person speak when she doesn’t have an intellectual’s vocabulary? How can someone who is innately poetic speak in a lyrical way when she only has the corrupted language of a shopping-mall society?

Your latest book, Under the Bridge, is nonfiction and explores teenage girls as well—girls who were involved in a murder. Why are you drawn to this age group?

Teenagers are unguarded; their emotions are more explosive and their situations are more precarious—so for a writer, at least for me, this provides powerful material. I’m also interested in exploring the forces that influence individual action, and teenagers are generally more vulnerable to these forces than adults.

Sara gets involved in crime in The Torn Skirt. Were the girls you met while researching Under the Bridge similar to your fictional creations?

Not at all. I was surprised when I met the girls who were involved in the murder of Reena Virk. I expected them to be more like the fictional “bad girls” of my imagination, but they were utterly different. They weren’t outcasts or misfits. They weren’t angry at the injustice or rules of their society. They were pretty and popular, very conformist and typical, yet they stole cars and wanted to be gangsters and engaged in this ruthless violence. I really had to work hard to figure out who they were, where they were coming from, because I’d definitely never known girls like that before.

The Torn Skirt has very passionate, devoted readers—there are websites with songs and poems written in honor of Sara and Justine. Were you surprised by this response? What type of fan letters do you receive?

I was surprised by the intensity of the reaction, but I think it’s because most books about teenage girls explore romance or fashion. This was a completely different kind of story. The letters are really moving and wonderful. Some are a little unsettling—one girl wrote lines of the book around the walls of her detox center; another copied out the entire book into her notebook because she had to return her copy to the library.

Do you think the Internet has changed life for teenage girls?