It's been more than a decade since "Amy," as she's known in court papers, was first sexually abused by her uncle. The abuse ended long ago and he's in prison, but the pictures he made when she was 8 or 9 are among the most widely circulated child pornography images online.

Now the 20-year-old woman is taking aim at anyone who would view those images and asking for restitution in hundreds of criminal cases around the country.

Her requests and those filed by other victims of child pornography are forcing federal judges nationwide to grapple with tough legal questions: Is someone who possesses an abusive image responsible for the harm suffered by a particular child? And how much should that person have to pay?

"It is hard to describe what it feels like to know that at any moment, anywhere, someone is looking at pictures of me as a little girl being abused by my uncle and is getting some kind of sick enjoyment from it. It's like I am being abused over and over again," Amy wrote in court papers.