Earlier quoted context omitted.
I know for slander, in the USA you're allowed to say pretty much anything as long as it's true. The UK has much stricter laws against defamation. (In the US, the victim might sue for damages, but that's not the same as criminal charges.)
Even in the UK the truth is a valid defense against a libel case. The main difference is that the burden of proof is put on the alleged libeller, who has to prove s/he hasn't committed libel, rather than on the person who has supposedly been libelled.
Basically if you act on good faith you are clear, even it isn't true. (Note that there are requirements that you took some measures to verify the legitimacy depending on your position).