The Old Fat One (sorry but you said it
mentioned
in the UK ...
For a pursuer to win a defamation action they must first prove that the written or spoken word is false (and the onus is on the pursuer). If they do prove it to be false, they still have plenty of other hurdles to get over as well. If they cannot prove it is false, they lose.
Sadly, in England and Wales, you have the exact wrong end of the stick. I learned a little about English Libel law when following the Simon Singh case and for the defendant (the one defending the allegation of libel) the position is horrific. The burden of proof is on the defendant. The claimant (alleging libel) can claim any meaning that they choose to the words published and the defendant then must successfully defend the claim (of libel) to win. At the extreme, if you don't turn up in court you simply lose. The claimant has to prove nothing. Exactly nothing at all.
Please see the reference[1] for a proper explanation from a lawyer:-)
The legal costs are horrendous (£500k-£1M) and in general not all costs can be recovered from the losing party. Mr Singh has estimated that he may be out by £50k or more at the end of the day even though he has been awarded costs and even though the case did not get as far as a trial. The total costs have been estimated at £300k for both parties.
The claim (of libel) in this case was based partly on claiming that the word "bogus" meant something like deliberately and dishonestly and fraudulently deceitful. The court of appeal eventually dismissed such a strong meaning "In its context the word is more emphatic than assertive".
The next worry is that the burden of proof is "balance of probabilities" (not exactly sure about this - sorry). Even if you are correct it is easy to lose.
This was illustrated in the Singh case by the difference in the judgements reached in the original ruling on meaning and the appealed ruling on meaning. It was breathtaking. That two successive courts could reach such divergent conclusions on the same case is most disturbing.
Finally there are no-win-no-fee legal firms out there who may think it worth raising a claim even if the claimant has no money.
In England mentioning anyone in print (including on-line) is hazardous to your wallet.