Are you a lawyer? No? Then don't make legal threats against other Wikipedia editors. "No legal threats" is an official site policy, and you will almost certainly be blocked from editing if you do this.
What's that? You say, you are a lawyer? Well, that's fine. But you're still going to be blocked if you try it. Threatening a lawsuit can create a chilling effect on the editing process, and it just makes everyone unhappy.
This isn't to say you should avoid referencing anything legal: pointing out that plagiarism violates copyrights, for example, or suggesting that an unverified claim may be libelous. That isn't the same as making a threat.
And every once in a long while, official action is necessary to put thins right. But in these cases, you're better off bringing it to the attention of the Wikimedia Foundation, instead of scaring some poor Wikipedia editor.