Twitter users: A guide to the law

While Twitter users in the U.S. are used to being free to tweet whatever they want, European tweeters aren't as lucky.

"People who tweeted photos allegedly of child killer Jon Venables are being charged with contempt of court. It's the latest in a long line of cases that suggest that ordinary social media users need to have a grasp of media law.

"Journalists from traditional media are used to going on courses and reading works like McNae's Essential Law for Journalists. Those regularly covering court may have another level of knowledge. But the final resort is always to the expert advice of a media lawyer.

"Here are some of the categories of law on which social media users in England and Wales are coming unstuck: libel on Twitter, reporting sex offences, breaking a court order, other contempt of court, threats, offensive comments, injunctions and super-injunctions."

Read more about Illegal tweets on BBC News.