dissenting:
I respectfully dissent from the majority’s conclusion that the trial court erred when it failed to strike Harmon’s opinion that “subtracting any albuterol that measured on the Intoxilyzer 5000[,] the reading would not have equaled or exceeded .10” (297 Ill. App. 3d at 10). The majority reaches this conclusion by reviewing Harmon’s complex scientific testimony and then playing the role of a fact finder. I simply do not agree with the majority’s approach, and I believe that any deficiencies in Harmon’s testimony were a matter for the trial court to consider. Accordingly, I would affirm the trial court’s decision to admit Harmon’s expert testimony.
It is well settled that an expert’s opinion is only as valid as the bases for that opinion. Gyllin v. College Craft Enterprises, Ltd., 260 Ill. App. 3d 707, 715 (1994). An expert is a witness who, because of his education, training, or practical experience, possesses knowledge beyond that of the average person. People v. Novak, 163 Ill. 2d 93, 104 (1994). The decision to admit an expert’s testimony lies within the sound and wide discretion of the trial court. People v. Eyler, 133 Ill. 2d 173, 211 (1989). It is a well-established principle of appellate review that this court does not substitute its judgment for that of the trier of fact on questions involving the weight of the evidence or the credibility of the witnesses. People v. Van Brocklin, 293 Ill. App. 3d 156, 165 (1997).
In this case, the majority criticizes Harmon for never explaining what portion of albuterol exits the body through exhalation and what portion of albuterol remains in the body. Given the sequence of events on the night in question, Harmon’s testimony that any albuterol would remain in defendant’s lungs for between two and four hours, and information from the product insert, the majority concludes that “some” of the albuterol defendant inhaled would have already been eliminated at the time of the test. Based on its own interpretation of the facts, the majority is then able to conclude that Harmon’s testimony was filled with “serious flaws” and not credible on appeal. In other words, by merely reading the record, the majority is able to contradict Harmon’s conclusion and the trial court’s determination regarding the amount of albuterol in defendant’s system and its effect on the Intoxilyzer.
As is apparent, the majority’s analysis is based on its reading of Harmon’s testimony and its credibility determinations of Harmon and defendant. These types of decisions are simply not the responsibility of this court. Harmon’s testimony was highly technical and certainly beyond the ken of the average person. His testimony was properly admitted because it would assist the trier of fact in the determination of a fact at issue, namely, the effect of albuterol on the Intoxilyzer reading. His opinion that the reading would be lower than .10 if the albuterol were to be subtracted was based on his knowledge and practical experience. Once he offered his opinion, the trial court had the discretion to determine whether that opinion was properly based in fact. It was also within the trial court’s discretion to weigh the value of that opinion as well as the credibility of Harmon and defendant. Because the majority has usurped the trial court’s role regarding the weighing of evidence and the determination of witness credibility, I dissent.