Toxicology results can be important but are not always definitive proof of impairment because they show presence of substances or metabolites, not necessarily impairment at the time of driving. Interpretation depends on timing, metabolism, and the specific substance involved. Defense work often challenges the reliability of testing, the chain of custody, and whether the results actually correlate with impairment during driving. Laboratories that process samples must follow validated procedures, and any deviations can undermine the weight of results in court. It is also common to seek independent testing or medical analysis to interpret results in context of prescription use and typical metabolite timelines. This helps distinguish therapeutic presence from impairing levels and provides a factual basis for challenging prosecutor claims about impairment. Accurate interpretation of toxicology findings is a technical area that often requires careful review in Florence cases.