Plant-based evidence has been an important component in solving crimes for centuries. Modern techniques and facilities have made plant evidence more important and useful than ever, and there are some stunning examples of trials where plant evidence played a critical roles in the outcomes. We will blend criminal cases and plant science in this course. We will review important cases that have involved and even depended upon significant plant-based evidence. Along the way, students will learn, at the introductory level, the plant science needed to appreciate the importance of plant-based evidence in crime solving. An overriding but intrinsic theme will be how the scientific method is useful and integral to applying logic to a body of plant-based evidence in specific cases.