[Solved] State Follows Model Rule

You receive an email from the other side of a negotiation which you know was not intended for your viewing.  Assume the Rules of Professional Conduct governing attorney behavior in your state follows Model Rule 8.4(c), which says “it is professional misconduct for a lawyer to engage in conduct involving dishonesty, fraud, deceit or misrepresentation.” Does this apply, and if so, how?  From a Christian standpoint, what might be the best course of action?