Experience • Integrity • Tenacity • Results

How drug recognition experts determine impairment for DWI

On Behalf of | Apr 1, 2021 | Drug Crimes |

There are many people in the Houston area who drink alcohol. Most also know that it is illegal for them to drive after they drink too much. They may also know that they there are breathalyzers that are used to determine the blood alcohol concentration (BAC) in a person’s system. If the BAC is above .08, they can be charged with a DWI. It is also illegal to drive while people are under the influence of drugs as well, but unlike being under the influence of alcohol there is not an easy breath test to determine whether they are under the influence of drugs.

In order to determine whether a person is under the influence of drugs at the time they are driving, police rely on drug recognition experts. These are generally police officers who have been trained to observe different cues to determine whether the person is likely under the influence. Eventually a blood or urine test will be used to determine whether there is a presence of drugs, but before they can test in that manner, there must be at least probable cause that they are under the influence and that generally is based on the drug recognition expert’s observations.

Factors used to determine drug impairment

There are a number of indicators that drug recognition experts look for when determining impairment. These include, but are not limited to:

  • Talking with other officers to determine the driving conduct of the driver
  • Administering field sobriety testing such as walking on a straight line
  • Checking pupil sizes in different lights
  • Checking blood pressure, temperature and pulse
  • Speaking with person to ask questions about if they consumed drugs, how much they ate and other questions to determine responses
  • Checking for injections points in the body

There are many people stopped and arrested in Houston on suspicion of being impaired by drugs. The initial arrest is based on drug recognition experts opinions and observations. These can be challenged though and if the observations were inaccurate the person may be able to avoid the harsh penalties that come with a DWI conviction. Experienced attorneys understand these defenses and may be able to protect one’s rights.


FindLaw Network
Avvo Rating 10.0 Superb Top Attorney Criminal Defense | Reviews Charles T. Ganz Avvo | Avvo Rating 10.0 Charles T. Ganz Top Attorney
Rated By Super Lawyers | Charles T. Ganz | Selected in 2017 | Thomson Reuters
Rated By Super Lawyers
LC | Lead Counsel Rated
The National Trial Lawyers | Top 100 | Trial Lawyers
Martindale-Hubbell | Client Champion | Gold 2020