Collecting written testimony, documents, and other evidence used in trial is called

This is called evidence

discovery.

Explanation: Once the complaint and answer have been exchanged, the next phase of litigation, called discovery, begins. Discovery is a way of collecting written or oral testimony, documents, and other evidence that can be used at trial. The civil rules of procedure give litigants (parties to a lawsuit) power to compel each other and nonparties to answer questions and provide documents relevant to the lawsuit. During the discovery phase of the case, attorneys for both sides are busy collecting evidence. PF