As any ardent tweeter knows, you can pack a lot into 140 characters. Enough indeed to land you in jail for nearly two months, as Swansea University student Liam Stacey has found to his cost. Those that think the micro-blogging platform provides any semblance of anonymity should sit up and take note.
Stacey was found guilty of posting racially offensive comments on the site, relating to Bolton Wanderers footballer Fabrice Muamba, after he collapsed on the pitch during a recent FA Cup match with Spurs.
Police were knocking on Stacey's door to question him about the comments within days.
While there's been near-universal revulsion at Stacey's comments, the 56-day sentence imposed underscores the hard line taken by the authorities over what gets posted on social media.
Earlier this week, a cross-party committee of MPs published their report into privacy and injunctions, in the wake of numerous online breaches of court orders, often by people posting under a pseudonym on Twitter.
As the MPs noted, Twitter will readily unmask its users and hand over all account information when presented with a court order.
Stacey isn't, of course, the only person to appear in court because of comments made on social media.
Last year, two men, Jordan Blackshaw and Perry Sutcliffe-Keenan, were jailed for four years for inciting riots on Facebook.
And Paul Chambers' case has become something of a cause célèbre, after his tweet about blowing up Robin Hood airport landed him with a hefty fine.
Anyone viewing Twitter as just a repository for throwaway comments should think again.
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