Hi, thanks for your question. My name isXXXXX can help with this.
Do you just want the posts taken down or do you want to sue for damages?
Okay. Contact facebook and tell them about the posts, they're likely to just remove them if they're potentially defamatory.
Then, to obtain compensation, you would have to issue a claim at court. You would need to do a detailed pre-action protocol letter to the former pupil first.
Here is the protocol, you must follow this before suing: http://www.justice.gov.uk/courts/procedure-rules/civil/protocol/prot_def
It tells you what information needs to go in your letter of claim etc.
Most people settle at this stage, and you should hopefully get a sensible financial offer from the former pupil (or his/her parents) before you have to issue a claim.
OK If I had to go ahead with a claim what are the likely costs?
Depends - you can get solicitors that would do this type of thing on a no win no fee.
But if you paid privately, all the way to trial, it could cost £30k, possibly more.
It all depend.
I'd look for solicitors that would do it on a no win no fee agreement.
Very few cases ever reach trial though. Don't forget, the defendant is likely to incur such costs if they have to defend with lawyers.