Be careful what you post online — it could come back to haunt you.

This has been popular advice for a while now, repeated by a chorus of onlookers and pundits each time a public figure is called to task over a controversial comment posted online.

Politicians and public figures face their fair share of scrutiny, but it is average teens that seem to bear the brunt of this perilous landscape.

Teens are coming of age, experimenting with their identities and figuring out personal relationships — all against the backdrop of social media and instant messaging and the possibility that any online communication could become public fodder.

Despite the fact that the internet has been around for decades, this is still fairly new territory without clearly defined rules, says MIT professor Sherry Turkle, author of Alone Together: Why We Expect More from Technology and Less from Each Other.

"The blunders that come hand in hand with growing up are going to live on the internet forever, essentially making the moratorium for youth almost non-existent," she said.

No 'moratorium for youth'

But what is the line between youthful blunders and truly harmful behaviour?

There have been numerous stories recently in which teens have received severe punishments in response to questionable online activities.

Harvard University rescinded admission offers to 10 students based on comments and memes in an obscene Facebook group. Meanwhile, because of a new bill passed by the U.S. House of Representatives, a person under 18 caught sexting could face 15 years in prison.

While the two cases are quite different, both are examples of attempts to bring order to the digital Wild West.

Matthew Johnson, director of education for MediaSmarts, says that in the Harvard case, "the primary goal was to avoid admitting students who had shown that they were likely to behave in ways that might make other students feel uncomfortable or unwelcome."

He says the sexting bill, on the other hand, is clearly intended to send a message to producers and distributors of child pornography, which some point out also includes teens who are consensually sharing sexts.

According to Danielle Citron, a professor at the University of Maryland Carey School of Law, and a leader in the fight against online harassment and revenge porn, there need to be repercussions for harmful online behaviour, just as there are consequences for the offline equivalent.

There have been numerous stories recently in which teens have received severe punishments in response to questionable online activities. (iStock photo.)

"It's true that we are in the early stages of learning about the harm that can result from online behaviour, but we should view what happens online and off the same way."

She says "to not hold students to some level of accountability or to say it's no big deal is wrongful and misses an educational opportunity."

Teens don't fear punishment

But Johnson adds that for repercussions to have any effect, they have to be made public and have to be part of a consistent policy.

In other words, creating a healthy culture where teens can learn by example is far more beneficial than punitive rules meant to scare them from engaging digitally.

"In general, teens aren't much motivated by the fear of punishment. They're much more likely to be influenced by what they see as the norms and values of their community – particularly their peers and role models," says Johnson.

In fact, in some cases, a punitive approach might do more harm than good.

"The evidence is absolutely clear that taking a punitive approach does not work in convincing youth not to send sexts," says Johnson. "There's reason to believe that it actually makes things worse for those who are victimized when sexts they've sent are shared more widely without their consent."

Not only can fear of prosecution make teens afraid to turn to the law for help, but it also encourages others to blame the victim rather than the person who redistributed the sexts.

"This tendency to deny youth agency mostly comes out of an instinct to protect them," adds Johnson.

Citron says the "law can be stupidly or foolishly enforced" but that "we are in dangerous territory if we start carving out states of exception of social behaviour where we say, 'Ah, you're young, you didn't know better.' We are far beyond that in terms of how pervasive our networked tools are."

These are complex issues, especially considering that those making the decisions, or laws, didn't themselves grow up in this unique era in which any post is a swipe away from going viral.

"Unfortunately, it actually has the effect of making them less able to manage the risks they encounter," says Johnson.

Which means that while the decision-makers are opting for new rules and legislation, perhaps the bulk of the effort should be more preventative and proactive — namely, making sure teens are involved in conversations about negative online behaviour at home and in the classroom, and giving them a platform to have their voices and concerns heard.

Growing up constantly connected, teens are essentially the canary in the 21st-century coal mine. Having spent most of their lives online, they will ultimately show us the long-term effects of saying — or sharing — too much online.

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