Anyone in Virginia who is stopped by an officer while driving and then suspected of being impaired by alcohol may be asked to perform some tests at the location where they have been stopped. These are commonly referred to as field sobriety tests due to the location at which they are administered and because they are designed to get some assessment of a person's sobriety or impairment.
As explained by FieldSobrietyTests.org, none of these tests can prove that a person is drunk nor can they measure any level of intoxication. They are instead used to support the possibility that a person is impaired, thus allowing an officer to place them under arrest for suspected driving under the influence.
It is important to know that many physical or mental health conditions may interfere with a driver's ability to pass these tests. Two of the tests assess a person's ability to balance, something that may be difficult for a person who is very overweight, over the age of 65 or who has injuries to their feet, knees, back or other portions of their legs. Inner ear problems can also interfere with a person's ability to balance as required by the walk-and-turn or one-leg test. These same tests also look for a person's ability to multitask and follow complex directions but some people may not be able to mentally understand the test instructions.
Very Well Mind adds that drivers who wear contacts might not be able to pass the horizontal gaze nystagmus test because of the presence of the contact lenses.