The phrase “duces tecum” is Latin for “bring with you.” It is most commonly seen in the sense of a subpoena duces tecum, a formal summons which orders someone to bring materials to court or face punishment. This can be compared with a subpoena ad testificandum, which compels someone to go to court to provide testimony for a case. A subpoena duces tecum can be issued to one of the parties in a case or to someone who is believed to have materials which may be relevant to the case.
When someone is served with a subpoena duces tecum, the document must include a clear description of the types of materials which need to be brought to court. Parties to a case are not allowed to utilize a subpoena duces tecum to “go fishing” for evidence. The document must be issued to someone with a reasonable belief that he or she is holding documents or other materials which could be important in the case.
Privilege applies to certain people issued with such a subpoena. Under attorney-client privilege, for example, an attorney can withhold a number of documents including materials used to prepare for the case. Likewise, doctor-patient privilege comes into effect in these situations and certain other communications may be protected as well. If there is a belief that turning materials over would violate privilege, the target of a subpoena can consult a lawyer for advice.
The subpoena duces tecum can also be used to obtain evidentiary material from people who are summoned to attend a deposition. The target is asked to bring the material along to the deposition for examination. Not all of the evidence collected in this way will be used in court, but it can help to build a case and may provide information which could be highly relevant to the arguments which will be used in court to defend or prosecute a case. It should be noted that the rules of discovery apply to materials obtained under a subpoena duces tecum.
In some regions courts have made an effort to remove Latin from legal terminology, using plain language to make the nature of a legal activity clear to someone who may not be familiar with Latin. The widespread use of Latin in legal terms is unlikely to vanish entirely in languages such as English, however, especially given that so many Latin words are already in use in English.