Forensic science expert witnesses interpret physical and chemical evidence for the court. The experts listed here cover forensic toxicology and drug-test interpretation (urine and hair), the effects of alcohol and drugs on behavior in criminal and civil matters, psychopharmacology, and forensic document examination, including handwriting and signature authentication in contested wills, contracts and fraud cases. Typical engagements include DUI and impairment cases, workplace drug-testing disputes, questioned-document authentication, and postmortem toxicology review.
No published survey breaks out toxicology or document examination separately, so the best available benchmarks are the all-field figures: an average of $465 per hour in the 2026 ExpertPages survey, medians of $450 (review), $475 (deposition) and $500 (trial) in SEAK's 2024 study of more than 1,100 experts, and placement averages of $356 / $448 / $478 from the Expert Institute. Ask each expert for a written fee schedule; most in this field quote a minimum engagement fee, which 74% of experts now require. Sources are in the 2026 fee guide.
Credentials to look for: board certification in forensic toxicology (ABFT or equivalent), CFDE or board certification for document examiners, and a record of prior qualification as an expert in the relevant court.