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Maryland Department of State Police

Chemical Test for Alcohol Unit

The Chemical Test for Alcohol Unit (CTAU) manages the state’s alcohol and drug testing and training programs for impaired driving enforcement including

  • Chemical testing for suspected impaired drivers and
  • Training that relates to the detection, apprehension, and processing of drug and alcohol impaired drivers.  

Annual statewide DUI arrest totals

  • 2023

    12,917

  • 2024

    12,595

  • 2025

    13,242

Chemical testing includes three parts: 

  • Breath tests for alcohol
  • Blood tests for alcohol
  • Blood tests for drugs

The unit does not test samples themselves but administers the programs, processes the analytical paperwork, and maintains the blood results. The blood specimens are tested by the Forensic Sciences Division.

Maryland State Police mobile breath testing van
MDSP mobile breath testing van for DUI enforcement

CTAU offers training services to Maryland officers for detecting and managing impaired drivers, including:

  • DWI detection and field sobriety tests
  • Using breath testing devices
  • Managing sobriety checkpoints
  • Recognizing drug impaired drivers

Training sessions are also offered for judges and prosecutors. The unit fulfills presentation requests from citizen and organizational groups whenever feasible. 

Celebrate the founders of Maryland's Breath Testing Program

The Chemical Test for Alcohol Unit hosted Wheels of Warning to celebrate Maryland’s breath testing program and honor its legacy.

Questions