Never overstate your case. Be Scrupulously accurate
Once you have worked long and hard on your case – and have decided not to settle – you’ll probably be utterly convinced that your side is right. That is as it should be. But the judges haven’t worked on the case as long (or, probably, as hard) and are likely, initially at least, to think it much more of a horse race than you do. That will be true in any case, but especially when discretionary review has been granted to resolve a divergence of views in the lower courts. You’ll harm your credibility – you’ll be written off as a blowhard – if you characterize the case as a lead-pipe cinch with nothing to be said for the other side. Even if you think that to be true, and even if you’re right, keep it to yourself. Proceed methodically to show the merits of your case and the defects of your opponent’s – and let the abject weakness of the latter speak for itself.
Scrupulous accuracy consists not merely in never making a statement you know to be incorrect (that is mere honesty), but also in never making a statement you are not certain is correct. So err, if you must, on the side of understatement, and flee hyperbole. Since absolute negatives are hard to prove, and hence hard to be sure of, you should rarely permit yourself an unqualified “never”. Preface a clause like “Such a suit has never been brought in this jurisdiction” with an introductory phrase like “As far as we have been able to discover, . . . . ”
Inaccuracies can result from either deliberate mis-statement or carelessness. Either way, the advocate suffers a grave loss of credibility from which it’s difficult to recover.
Reference: Antonia Scala and Bryana Garner