An Unusually High Cocaine Blood Concentration in an Impaired Driving Investigation.

Cocaine is an illicit drug frequently encountered by forensic practitioners in driving under the influence of drugs (DUID) casework. Whole blood collected from a suspected drugged driver was found to contain 3.000 mg/L cocaine, 1.600 mg/L benzoylecgonine, and 0.260 mg/L methamphetamine. The high concentration of cocaine, while common in overdose death investigations, is unusual for an impaired driving case. Information from the officer revealed that the motorist swallowed cocaine during the traffic stop. Although a cocaine DUID charge could not be pursued, the blood methamphetamine concentration exceeded the State of Nevada "per se" limit for operating a motor vehicle. The motorist was successfully prosecuted for DUID based on his admission of using methamphetamine prior to driving and the blood methamphetamine result. This case highlights the importance of considering case history when interpreting laboratory results and the application of jurisdictional statutes as an approach to prosecuting suspected drug-impaired drivers.