Colorado law enforcement officers are always on the lookout for impaired drivers. Any time a driver appears to deviate from the norm, it is possible that an officer will spot such action and decide to stop the driver. Once this occurs, if the officer suspects that the driver has been drinking, he or she will likely ask the driver to perform voluntary roadside manuevers, more commonly referred to as field sobriety tests.

One of the tests the officer may perform is the horizontal gaze nystagmus (HGN) test. Utilizing this test, the officer will analyze the movement of the driver’s eyes as he or she follows a slow moving object, usually a pen light. Research indicates that officers who have been properly trained are able to accurately identify an impaired driver 88 percent of the time by utilizing this particular test.

Another test that the officer may ask the driver to perform is the walk-and-turn test. This test requires the driver to take a specific number of steps by walking heel to toe. The driver is to perform this task by walking in a straight line and then turn on one foot and return in the same way. Research indicates that drivers who struggle with this task have a 79 percent chance of being legally impaired.

The other test that the officer may ask the driver to perform is the one-leg stand test. This test requires the driver to stand while holding one foot off the ground. The driver is then instructed to count in a certain manner for a period of approximately 30 seconds. Research indicates that drivers who struggle with this task have an 83 percent chance of being legally impaired.

Prior to conducting such field sobriety tests, the officer should question the driver regarding any conditions that could prevent the driver from conducting such tests. For example, if the driver has an eye disease, the results of the HGN test could be tainted. Additionally, other Colorado drivers may suffer from injury or illness that can affect their equilibrium and make it difficult for them to maintain balance during these tests. For those accused of drunk driving based upon field sobriety testing and other evidence, representation by a criminal defense attorney is always adviseable in the resulting court proceedings.

Source: duijusticelink.aaa.com, “Standardized Field Sobriety Test“, Accessed on July 1, 2017

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