On Jan. 14, Phoebe Prince endured a day of taunts and text-message bullying at South Hadley High School. By all accounts, that day was a lot like the one before it, and the one before that, just like most days since Prince moved to South Hadley from Ireland.

But on Jan. 14, Prince went home and hanged herself.

And now nine of Prince's schoolmates, ranging in age from 14 to 18, face criminal charges of harassment, stalking, statutory rape, and violation of civil rights with bodily injury in connection with her death.

The charges are a bold move from law enforcement to use criminal prosecution to crack down on bullying. Prince's death follows two other high-profile suicides related to bullying, one of a Massachusetts boy last year and one of a 13-year-old Missouri girl who was sent harassing messages on MySpace by the mother of a classmate.

"Every law has its first case, and this is a legal issue that's ready for a test case," says Tamara Holder, a Chicago criminal lawyer who has worked with Chicago's public schools and police on school violence issues. "It looks like there's a trend, and that's the time to get out in front of a problem, legally."

If kids know they could be held criminally accountable for their actions, they may think twice, Holder says.

But whether bullying is actually a crime is a thornier question. A lot of kids are bullied, but very few kill themselves. And even in those cases, proving that the bullying was the direct cause of the suicide is hard, especially when, in the case of 13-year-old Megan Meier, the teen has a history of depression or other mental health issues. (Lori Drew, the woman who posed as a teenage boy and pretended to be interested in Meier, was eventually acquitted of all charges.)

Forty-two states have anti-bullying laws, according to the National Conference of State Legislatures, but most deal with prevention and the duty of school administrators to step in, not directly with the bullies themselves.

"Essentially, we're talking about people being mean to each other, and that's tough, though not impossible, to criminalize," Holder says. Holder notes that if it occurred between two adults, there would be nothing criminal about it.

But children are different, says Dr. Aoife Lyons, a child psychologist in Chicago who has spoken at schools about bullying. Lyons says she regularly sees children traumatized by bullying, some so severely that they require hospitalization.

"It may seem like minor bullying, but it doesn't feel that way to a child," Lyons says. "It's our job to protect kids from a lot of things, and sometimes that includes other kids."

Holder says she thinks the charges against the Massachusetts teens would pass legal muster, but that getting a conviction would require a finding that the bullying was the chief and immediate cause of Prince's suicide, which may be difficult.

No matter what happens in Massachusetts, Holder says, the legal system is starting to catch up with bullying.

"It's time to create a standard: What is bullying, and what are the legal obligations of everybody involved -- parents, teachers, kids?" Holder says. "At the end of the day, these parents sent their daughter to school, hoping that she would be protected. That didn't happen."