Justin Bieber has teamed up with MTV and Facebook to take a stand against cyberbullying.

The teen star called for young people to post an action to MTV’s Draw Your Line, a virtual map and support forum that tracks efforts to stop digital abuse. To spur participation, Bieber is offering a chance to win one of 14 prizes just by posting an action. The contest lasts until March 31.

Draw Your Line is part of MTV’s “A Thin Line” campaign, aimed at helping America’s youth to recognize and prevent digital abuse. Nearly 800,000 people have already taken action as part of the campaign. Facebook has also joined in, promoting the collaboration on its Facebook Safety Center.

It’s an interesting choice to pick Bieber for a campaign against cyber bullying. Aside from being a teen himself (and having a new movie to promote), Bieber himself is often a prime target of digital abuse (cough, trolls) and web pranks. He has become an unwitting and unexpected representative for dealing with cyberbullying.

The contest promises to raise awareness and encourage submissions to Draw Your Line, but it’s difficult to measure the actual outcome. It’s nearly impossible to gauge the validity and veracity of claims like “I just watched a video about digital abuse” or “I just spoke to someone about cyberbullying.” There is also no limit on the amount of times an individual can post to the website. Given the fervor that Bieber usually creates, it’s possible that Draw Your Line could receive a fair share of spam from people just wanting to win prizes like a personalized voicemail greeting.

It’s a tough balance and one that has more to do with the teen star’s haters and admirers than his intention to do good. Bieber brings much deserved publicity to the real threats of cyberbullying, but avid fans could also outshine the site’s core message as they clamor for prizes.

So far the responses seem positive, but what do you think? How can you verify participation in a crowdsourced app? What are the pros and cons of a celebrity endorsement? Let us know in the comments.

Image courtesy of Flickr, Jenn and Tony Bot