A young attorney at our firm recently took his oath as a new attorney. The Chief Justice of our Supreme Court exhorted his class to "seek justice," but acknowledged that, for many, their first years of practice would be spent reviewing boxes of documents. The young attorney's father, a wise general counsel who litigated for many years, turned to him and whispered, "You'll find justice in box 253." He is right. The devil is in the details and so are the devil's lies.

It never ceases to amaze us how witnesses, including many in positions of authority and trust, will lie - and more so, how they think they will get away with it. Sometimes the lie is not even central to their defense, but they will gamble their credibility and lose. They may not be used to having their accounts scrutinized or challenged. They may have fallen into the habit of embellishing and fabricating details to promote their story. But the truth has a way of coming out on cross-examination, and when you catch your opponent in a lie, it destroys their credibility. Cases often turn on finding the one document or eyewitness that proves the lie.

In a case we tried decades ago - one of our first in federal court as young attorneys - the opposing party's counsel claimed they had sent a letter rejecting a contract offer that our client was certain he had never received. Our client was certain that the letter had not been written or sent - because the opposing party had verbally consented to the contractual offer on the very day of the letter and had been enthusiastic about the offer. But we appeared to have a classic credibility contest over what was said that day - and whether this letter was written or sent as dated. The letter, on its face, appeared to be more persuasive evidence than our client's recollection of events. Opposing counsel stood up in opening statement and said the letter would prove convincingly that there was no agreement. We stood up and said that we would prove, to a moral certainty, that the letter upon which their case rested was counterfeit - a fraud - drafted and back-dated a whole year after the events at issue.

How? This was in the days when law firms listed all the attorneys in their firm on their letterhead. And on the letterhead of this sham letter was a person who was not admitted to practice law until a year after the date of the letter. That person was our first witness - called pursuant to subpoena - and he testified that he had not been admitted to practice until a year after the date of the letter bearing his name as an attorney on the letterhead. The jury awarded punitive damages. The find of his name on the letterhead came late at night - a few days before trial started - as we were thinking that there must be some means to establish the truth, and as we stared at the letter for the clue.

In other trials, we have demonstrated that a CEO didn't sign and send a billion dollar offer as he testified, that a witness was paid money to lie to federal investigators and that another planted evidence to incriminate our client. These and many similar experiences leave us convinced that culprits leave fingerprints - there is no perfect crime. But it takes perseverance and attention to the details to find the proof. And before the lie can be proved, the story must be pinned down so that it can't be changed when the counterproof is found. How to find the smoking gun? A few helpful suggestions:

• Pin down the details of your adversary's story. Who typed the letter? Who reviewed it? Where were they when they sent it? What did they do immediately before they composed it? What did they do immediately after? Who was with them? Who did they discuss it with? How did they get to their location? What car did they travel in? How long were they there? How was a copy of the document filed or saved?
• Talk to multiple witnesses about what really happened. Don't accept vague answers. Refresh recollection. Let them know that if they lie to you, they will be exposed.
• Review all documents that are near in time to the critical events. You may find your witness was engaged on another call or matter when they claimed to be taking the disputed action.
• Carefully challenge all assumptions and premises. Challenge your own client's account and make sure they have carefully reviewed any document or source of information that could refresh their recollection before you rely on their memory for the truth.
• Never give up on the truth. We believe in the power of the courtroom, the power of cross-examination and the power of the jury's ability to tell truth from lie.

You will only find the smoking gun if you search exhaustively for it - and never lose the conviction that it's there, buried in box 253, waiting to be found.

Craig C. Martin and David J. Bradford are Co-Chairs of Jenner & Block's Litigation Department.

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