What tests are used to determine impairment in a DWI stop?

The determination of impairment during a DWI stop is commonly conducted through breath, blood, or urine tests. These methods are essential for measuring a driver's blood alcohol concentration (BAC) or the presence of drugs in the system. Breath tests, such as those conducted with a breathalyzer, provide immediate results regarding alcohol levels. Blood tests can offer a more precise measurement and are often used when law enforcement suspects drug use in addition to alcohol. Urine tests may also be employed, especially if the individual has been using substances that may not be detected through breath testing.

The importance of these tests lies in their ability to provide objective evidence of impairment, which is crucial for enforcement purposes and legal proceedings.

The other response options focus on variations that either limit the types of tests used or include assessments that are not standard in determining driving impairment. Thus, the option that includes all the commonly accepted methods—breath, blood, or urine tests—accurately reflects the comprehensive approach that law enforcement takes to assess impairment during a DWI stop.