SOCIAL media has revolutionised our lives.

It has also created potential legal liability for any of us who use it.

Just ask Sally Bercow, who made a comment about Lord McAlpine on Twitter. Who would have thought that a few words posted on Twitter would have led to such a major storm which created probably the most high profile class action in reverse ever seen in the UK.

I say in reverse, because most class actions in law have several pursuers, but here, it was those who 're-tweeted' - repeated - her words, who ended up paying compensation or apologising.

Until recently, it was always thought that only newspapers who would end up being sued in the high profile libel trials. That no longer applies. Why?

First, any statement which lowers someone's reputation, and which can't be proven to be true or regarded as fair comment, is actionable in Scotland. If it appears online, it is treated as a publication in the same way as a book or newspaper article, and can lead to legal action more or less anywhere in the world.

Secondly, online posting frequently involves rash comment and often made out of context. Perspective is critically important in defamation laws, as the lack of it can change the whole meaning. Third, social media actively encourages repeating or sharing of other people's words. That creates a potential trap.

Repeating a defamatory comment is as actionable as making the original statement and so a 're-tweet' or sharing on Facebook could lead to legal action.

We all have to be very cautious in what we say. I have seen a rise in inquiries looking to have articles or comments removed from social media sites or blogs. I anticipate the trend will continue.

David McKie is a partner in Levy and McRae solicitors and is Head of Media Law at Glasgow University