Forensic botany: using plant evidence to aid in forensic death investigation.

Forensic botany is still an under-utilized resource in forensic casework, although it has been used on occasion. It is an area of specialty science that could include traditional botanical classification of species, DNA, ormaterials evidence (trace and transfer evidence), crimemapping or geo-sourcing, all dependent on the specific case application under consideration. Critical to the evaluation of plant evidence is careful collection, documentation, and preservation for later scientific analysis. This article reviews proper procedures and recent cases where botanical evidence played a role in establishing eithermanner or timeof death. Plant evidence canbeuseful for determining if a deathwasdue to anaccident, suicide, or homicide, or what time of year burial may have taken place. In addition, plant evidence can be used to determine if a crime scene is a primary or secondary scene and to locatemissing bodies. Ultimately the value of botanical evidence in a forensic investigation will depend on what transpired or was overlooked at the crime scene. Scientists will not be able to use their plant analysis to resolve a critical issue if the investigator or crime scene technician failed to start the process. At the core of this foundation is a requirement that investigators’ recognize the relevance of plant material, properly document where it was found, establish its relationship to the surroundings, and conduct suitable collection and preservation techniques (1) (Fig. 1). Seemingly one of the easiest tasks at a crime scene, recognition of pertinent evidence, is in practice one of the greatest challenges. The genesis of this problem lies in the reality that what is relevant at today’s scene may or may not be relevant tomorrow. Thus, neither institutional knowledge nor checklists will provide a crime scene investigator with the requisite skills, ensuring that all key evidence is recognized. Moreover, whereas experience is of great value, it alone will not dictate the relevance of a particular item of evidence to that specific investigation. In the case of botanical evidence, this problem is exasperated by the general lack of knowledge of this subject matter. Plant Evidence Collection and Preservation Overcoming a potential recognition problem is best accomplished by making crime scene personnel aware of the possible value of plant evidence and sharing successful case examples (2-6). However, several of these case stories in 606 www.cmj.hr FORENSIC SCIENCE C r o a t M e d J 2 0 0 5 ;4 6 ( 4 ) :6 0 6 -6 1 2