Legal Definitions - ad testificandum

ad testificandum is a Latin phrase meaning "for the purpose of testifying" or "to testify." In legal contexts, it refers to a court order or writ that compels an individual to appear in court or at another legal proceeding specifically to provide testimony. This testimony can be about facts they witnessed, their expert opinion, or other relevant information.

Here are some examples illustrating how this term applies:

• Scenario: Witness in a Civil Trial
  Imagine a person who was walking their dog and witnessed a car accident. The attorneys for the drivers involved in the collision need this individual to recount what they saw in court. The court would issue a subpoena ad testificandum, which is a legal document ordering the pedestrian to appear on a specific date and time to give their account under oath.

  This illustrates ad testificandum because the pedestrian is being legally compelled to appear specifically for the purpose of testifying about the events they witnessed.

• Scenario: Incarcerated Individual as a Witness
  Consider a situation where a person currently serving a prison sentence holds crucial information relevant to a separate criminal trial involving a former associate. To ensure their presence and testimony, the court would issue a writ of habeas corpus ad testificandum. This writ directs the prison authorities to bring the incarcerated individual to the courthouse so they can provide their testimony in the ongoing trial.

  Here, ad testificandum applies because the writ is specifically issued to bring the prisoner out of custody to testify in another legal matter.

• Scenario: Expert Witness Deposition
  In a complex product liability lawsuit involving a faulty medical device, the plaintiff's attorney wants to obtain the testimony of a renowned biomedical engineer who is not directly involved in the case but can offer an expert opinion on the device's design flaws. The attorney serves the engineer with a subpoena ad testificandum for a deposition, which is an out-of-court sworn testimony.

  This demonstrates ad testificandum because the engineer is being compelled to appear at a deposition to testify by providing their professional expert opinion relevant to the case.