Earlier quoted context omitted.
Truth is an absolute defense to the claim of libel or slander in the US, but not in all worldwide jurisdictions.
It's also the case in the UK. What makes you think I was thinking of US libel law? I'm not American
I referenced US libel law as a counterpoint to the rest of the world because I thought you were not thinking of the US. There have been several high profile cases of journalists and scientists saying true but defamatory things in the UK about quacks and charlatans and being hounded in the courts. In response to this, the UK has actually passed legislation attempting to remedy the situation, but this has not yet taken effect.