A guy uses a forum to call someone a liar.
(He's traceable through a valid email address.)

He's not a troublemaker, he's not even trying to be anonymous; he is genuinely aggrieved and very very angry.

From my view point, it looks as though he has valid reasons for his outburst but the recipent of this attack is extremely wealthy and would no-doubt win any legal battle.

My initial thought is protect this poor guy and delete his comments to stop hime getting into trouble.

But that's not free speech!

However if his posts remain he is sure to be sued for libel.

Any thoughts on this very serious issue please?