Shirley Verschoor is a registered drug expert at the Netherlands Forensic Institute (NFI), where she works in the Illicit Drugs Department. With a professional background in pharmacy, toxicology, and chemistry, she combines analytical expertise with practical forensic casework.

Her work focuses on highly potent synthetic opioids, particularly nitazenes and related analogues emerging across Europe. She is actively involved in their analytical characterization, differentiation of structural isomers, and forensic interpretation in casework. Her daily forensic practice also includes elucidating the synthesis routes of other illicit drugs produced in clandestine laboratories, supporting intelligence gathering and evidential interpretation of complex criminal investigations.

As a drug expert, she prepares formal forensic reports for judicial authorities, providing independent and scientifically robust conclusions, and may be called to testify in court when required.