DWI Field Sobriety Testing

DWI Detection & Field Sobriety Tests (SFST’s)

There are three tests that are commonly administered to determine whether an individual is intoxicated. These are the Horizontal Gaze Nystagmus (HGN), the One Leg Stand (OLS), and the Walk and Turn (WAT). These tests were developed by the National Highway Traffic Safety Administration (NHTSA) and in 1981, law enforcement officers began to administer these SFSTs on individuals who were suspected of DWI.

1. Horizontal Gaze Nystagmus (HGN) Test

“Nystagmus” is defined to mean the involuntary jerking of the eyes. A horizontal gaze nystagmus is the involuntary jerking movement of the eye that naturally occurs in as an individual’s eye gazes to the side. When an person is impaired by alcohol, the jerking movement is exaggerated and can occur at lesser angles than if sober. Also, a person who is intoxicated will have more difficulty in tracking a moving object. When the officers are performing this test they are looking for 3 clues in each eye, with a total of six possible clues.

These clues are as follows:

• Lack of Smooth Pursuit: This means that the eye is not able to follow a moving object smoothly

• Distinct and Sustained at Maximum Deviation: This means that jerking is distinctly noticeable when the eye is looking as far to the side as it possibly could.

• Onset of Nystagmus Prior to 45 Degrees: This means the jerking began when the eye is within 45 degrees of centerIf the officer determines that you have four or more indicators, then the officer will determine that you are intoxicated. There are many ways to attack this test. The NHTSA manual is extremely specific about what an officer must do when performing this test. There usually is never a camera that could possibly observe the nystagmus in the eye. It is a test of opinion, and the police almost always say that you have failed. Attorney Sean Darvishi is knowledgeable in the law and able to attack any mistakes in the officer’s administration of the test, and the validity of the test.

2. Walk and Turn (WAT) Test

The Walk and Turn, as well as the One Leg Stand, is a divided attention test. There are two stages with the Walk and Turn: The Instruction Stage and the Walking Stage. Essentially, in the instruction stage the individual must begin with them standing with their feet in heel-to-toe position, keep their arms at their sides, and listen to instructions given by the police officer. The individual cannot begin before the instructions are completed. Then, the individual must take 9 heel-to-toe steps, turn in the way the officer tells them to, and take 9 heel-to-toe steps back. The individual must also count out loud and watch their feet. There are 8 clues that the officer will look for when administering this test.

These are:

• Can’t Balance During Instructions

• Starts Too Soon

• Stops While Walking

• Doesn’t Touch Heel to Toe

• Steps Off the Line

• Uses Arms for Balance

• Loses Balance on Turn or Turns Incorrectly; and

• Takes the Wrong Number of Steps

• Stand Straight

• Place Your Feet Together

• Hold Your Arms at Your Side

• Do Not Begin Until Instructed to

• Say That You Understand

• When Instructed, Raise Either Leg

• Approximately 6 Inches From the Ground

• Keeping the Raised Foot Parallel to the Ground

• Keep Both Legs Straight

• Look at the Elevated Foot

• Count Out Loud In the Following Manner:

  • One Thousand One, One Thousand Two, and so on until Told to Stop