Welcome to Legal Help
Home Missouri DWI Laws Field Sobriety Tests and Breath Tests in Missouri

Free Help – Ask Your DUI Questions

legal dui questions

Choose a State

Field Sobriety Tests and Breath Tests in Missouri

A law enforcement officer in the state of Missouri has the discretion to administer tests to a person they may believe was under the influence of alcohol or drugs while driving a vehicle.  A law enforcement officer has the right to use reasonable grounds in their analysis to determine whether or not a test is warranted.

Generally the first type of test administered in the state consists of the field sobriety tests by the National Highway Traffic Safety Administration.  These tests include the Horizontal Gaze Nystagmus Test, in which the driver is required to follow a light or finger with their eyes, the One Leg Stand balancing test, and the Walk and Turn Test.  It is important to know that a person is free to refuse to perform the field sobriety tests.  However, whether one decides not to perform the field sobriety test, or whether one consents to the test and fails, both can be used as evidence against the person during trial.  In addition, a failed field sobriety is not needed for an arrest, nor is the evidence needed for a conviction.  However, a failed test can only be added as extra evidence to a case against a driver suspected of a DWI and/or a BAC.

In addition, an officer may also ask a person to undergo a preliminary breath test before an arrest.  If one performs the test, the result can and will be admissible evidence and will be used against the person.  Studies have shown that the preliminary breath test device (PBT) may not be as accurate as the blood or urine devices so one may want to use caution before agreeing to volunteer to this test.   In addition, a person with asthma or another breathing or allergy condition may have difficulty performing a PBT and may will to avoid this test.  If one does indeed decide to refuse to perform a breath test, your refusal will be admissible evidence at trial.  In addition, your failure to comply could result in suspension of your driver’s license.  Thus, it is wise to think about the consequences on both ends before submitting or refusal of a breath test.


If you have any questions about speeding tickets, please ask them at our legal help forum. free legal questions

Ask Questions, Get Answers

free legal help forum

Contact a DUI Lawyer Today!