Forensic Chemistry, or “Drug Chemistry” is the forensic discipline of identifying evidence thought to be a controlled substance. Most often, the types of evidence the forensic drug chemist examines are pills, capsules, plant materials, tables, powder, drug paraphernalia and residues.
When an individual is prosecuted for possession or distribution of a controlled substance, the degree of the punishment and offense is often directly related to the amount of drugs identified in the case. It is the job of the drug chemist to accurately weigh the amount of substance, using a balance and then positively identify the drug in question.
The evidence is inventoried, often times photographed, and tested with a one or more techniques, including traditional spot tests, thin layer chromatography (TLC) and extraction, as well as instrumental techniques such as ultraviolet (UV) spectroscopy and gas chromatography (GC).
Advanced techniques such as Infrared spectroscopy (IR) or mass spectrometry (MS) are used to confirm the identity of questioned substances. Microscopy is also available for examining case material, such as marijuana. A report is issued to the investigative agency identifying any controlled substances amount detected. The Forensic Chemist is often required to testify as an expert in court to describe the methods used and the conclusions that were reached.