No real 'figuring' involved. In Discovery BOTH SIDES have to make copies of whatever evidence they plan to present at trial (They don't have to say HOW they'll present or argue it at Trial, but they have to make the other side aware of it.) And in fact one of the procedures that happens in pre-trial in front of a Judge is that both sides show the exhibits they WANT to use at Trial; and the Judge will rule whether the exhibit is okay/proper. It's not as draconian as It sounds because most stuff gets admitted with no objection by either party. But, when a contested exhibit comes up things between attorneys can get heated <--- And that's why they do this BEFORE a Trial and before the Jury is selected. No, one side or the other might still, raise an objection to an exhibit during trial if the other side presents it in a way that wasn't okayed/ or was in fact denied by the Judge Pre-trial. Also, it doesn't mean that if new evidence comes to light AFTER Discovery or during the Trial that it can't be introduced; BUT the side bringing it in must again provide copies to the opposing side; and there is usual a hearing outside the presence of the Jury to discuss it's introduction; and further, if's it's found that this was something one side or the other DID know about when the case was in Discovery, but didn't disclose it to the Judge or the other side; legal sanctions against the offending attorneys can occur; and if it's serious enough, it could be grounds for a mistrial. And if a mistrial was declared, it doesn't man the case is dismissed. It just means the Jury is dismissed; and depending on the situation, the case was most likely be re-tried from the start with a new Jury.