Preparation for testimony begins with a thorough documentation by the officer of what and how he/she performed at the crime scene and in subsequent activities related to the case, from chain of custody to the arrest of the accused. The report should be comprehensive and detailed so as to avoid omitting any activity and observations by the officer that might prove to be important to the case. All case material will be made available to the defense during the discovery process, and any evidence not properly documented and revealed to the defense during discovery risks being excluded at trial. Officer case reports should be examined by experienced officers to ensure they are complete and thorough. Before testifying, an officer should be familiar not only with his/her reports of personal activity but also with copies of lab reports, documentation of chain of evidence custody, reports filed by other officers connected with the case, dispatch logs, and the notes of criminal investigators. Although officers will usually know what questions will be asked by the prosecutor and be prepared to answer them, questions asked by the defense attorney in cross-examination can only be anticipated. Sometimes a question will be asked to which the officer has no immediate answer or recollection. When this happens, it is appropriate to answer, "I don't know. May I refer to my notes." In all cases, an officer must answer truthfully in accordance with personal knowledge and objective observation. Dress should be appropriate and traditional for court appearances, and demeanor should be calm and confident, devoid of nervous mannerisms, defiance, and anger. Books and other resources are suggested.