A Louisiana Subpoena To Testify At A Deposition In A Civil Action is a legal document issued by a court or other authorized body that requires an individual to appear and testify at a deposition in a civil action. A deposition is a type of legal proceeding in which one party has the opportunity to examine the testimony of another party under oath. The subpoena is a formal request that the individual appear and answer questions regarding the civil action. There are two main types of Louisiana Subpoena To Testify At A Deposition In A Civil Action: a Subpoena Ducks Cecum and a Subpoena Ad Testificandum. A Subpoena Ducks Cecum is a subpoena that requires the individual to bring certain documents or other tangible evidence to the deposition. A Subpoena Ad Testificandum is a subpoena that requires the individual to appear and testify at the deposition, but not necessarily bring any documents or other tangible evidence.