Case (cite)
People v. O'Neal, 254 N.E.2d 559 (App. Ct. Ill. 1969)
“The witness testified that he received the gun and bullet in question at the laboratory; and the gun and bullet were introduced into evidence. He also testified that he fired the gun twice, and that he compared the test bullets with the one in question. He testified to the procedure generally used and to the reasons why a comparison of bullets will reveal the identity of the gun which fired them. On the basis of these tests, he was of the opinion that the gun found on defendant’s person fired the bullet found in the complaining witness’s coat. The expert witness set forth the reasons for his conclusion, and it was for the triers of fact to determine how much weight to give to his testimony. It should also be noted that the bullet and gun in question were introduced into evidence, and that defendant was not foreclosed from conducting similar tests, either prior to or during trial.”
“Other jurisdictions also have allowed the conclusions of a ballistics expert even though demonstrative evidence had not been introduced. In McKenna v. People, 124 Colo. 112, 235 P.2d 351 (1951), the court held that the ballistics expert’s testimony was proper without the introduction of photomicrographs, stating that the latter were inaccurate to some degree. In State v. Wojculewicz, 140 Conn. 487, 101 A.2d 495 (1953), the court held that the introduction of the test bullet is not essential to the admissibility of the expert’s testimony. And in People v. Buckowski, 37 Cal.2d 629, 233 P.2d 912 (1951), it was held that the oral testimony of the ballistics expert as to the bullets in question was sufficient to support his conclusions.”