In People v. Park, 72 Ill. 2d 203, 209, 20 Ill. Dec. 586, 380 N.E.2d 795 (1978), the supreme court held that a police officer with only limited experience was not qualified to identify a controlled substance as cannabis. the court reasoned that the officer's personal observations of the substance were prone to error and that scientific tests were available to establish the identity of the substance. The court compared this process with an expert's ability to "draw fine distinctions" between fingerprints and ballistic markings and determined that, in these circumstances, the expert must possess some systematic knowledge of the scientific process. Park, 72 Ill. 2d at 211.