Dr. Wecht based his opinion on the fact that Workman was using a .45 caliber gun and hollow point ammunition and that such bullets fired from such a gun more than 90% of the time do not pass through the body but remain within the shooting victim. Dr. Wecht's professional opinion was that when hollow point ammunition fired from a .45 caliber gun does pass through the body of the victim, the exit wound is almost always larger than the entry wound. According to medical examiner Dr. James Bell, the exit wound on Lt. Oliver's body was smaller than the entry wound. Such a wound is consistent with the .38 caliber weapons being fired by the police.