Over the years, the legal community has come to disfavor “trials by surprise.” In times past, litigants in any dispute would “surprise” their opponents with witnesses and evidence on the day of trial. The other party would need to be resourceful to effectively combat the testimony or evidence presented. These days are gone: now, litigants in a criminal case must comply with formal rules of “discovery” that are designed to afford the parties (especially the defendant) a fair opportunity to learn the nature of the evidence the other party intends to present against him or her and to formulate a plan ahead of time to confront this evidence. This gives a criminal defendant a much better chance at achieving a favorable outcome in his or her case. See the article from NOLO about discovery in a criminal case.
General Principles of Discovery in a Criminal Case
A complete discussion of all of the rules of discovery applicable in a criminal case would be prohibitively lengthy. Instead, there are general principles that govern the discovery process with which defendants should be familiar. Knowing these principles can help you ensure your rights to be free from a “trial by surprise” are respected in your criminal case:
- Right to inspect. The prosecution must disclose materials in its possession to you and allow you a reasonable opportunity to inspect those materials. (The prosecution is not required to duplicate the evidence for you for free: the prosecution must merely make it available to you to inspect. You may be required to pay reasonable costs for copying or duplicating evidence if you want your copy.) A prosecutor’s office that fails to inform you that certain evidence exists promptly may be precluded from introducing that evidence at trial or (in extreme cases) may have its case dismissed.
- Exculpatory evidence. Any exculpatory and material evidence that is in the possession of the government must be turned over to you automatically. Exculpatory evidence can include evidence that either tends to exonerate you and prove your innocence or that would tend to reduce the sentence the court would otherwise impose upon you. Failing to turn over exculpatory evidence is treated very seriously. In some cases, the court will dismiss the criminal case entirely if the prosecutor fails to turn over exculpatory evidence. A prosecutor must turn over evidence he or she has in his or her possession along with any exculpatory evidence that any law enforcement agency has in its possession, whether the prosecutor knows of the evidence or not.
- Expert witnesses. A prosecutor must disclose to you whether he or she intends to use an expert witness in your case and, if so, the essence of that expert’s testimony. This is designed to give you an opportunity to depose the expert or hire your own expert, if you choose to do so. This also gives you the opportunity to prepare to challenge the prosecution expert’s opinion. Note that if you choose to use your own expert witness to rebut the prosecution’s witness that you may have a similar obligation to disclose the name of your expert and the essence of his or her testimony to the prosecution.
- Good faith. Parties to a criminal case have a general duty to each other to act in good faith toward one another. This means that they should attempt to cooperate with one another and not act deceitfully toward each other. This also requires the prosecution to respond promptly to your requests concerning specific items of evidence you want to view or inspect. A party who violates this general duty to act in good faith can be sanctioned by the court if the court determines a punishment is necessary.