TCOLE DWI Enforcement and Standardized Field Sobriety Testing 2

Question 1

During HGN, how far from the suspect's nose should the officer hold the stimulus?

Accepted Answer

12 to 15 inches

Answer

NHTSA standards place the stimulus about 12-15 inches from the nose and slightly above eye level.

Question 2

How long must the officer hold the stimulus at maximum deviation when checking for distinct and sustained nystagmus?

Accepted Answer

At least 4 seconds

Answer

The eye is held at maximum deviation for a minimum of four seconds to tell sustained nystagmus apart from end-point nystagmus.

Question 3

What is the maximum number of HGN clues an officer can observe in one suspect?

Accepted Answer

6

Answer

There are three clues per eye, for a total of six.

Question 4

Before scoring HGN clues, which preliminary check helps rule out a medical cause such as a head injury?

Accepted Answer

Checking for equal pupil size and equal tracking

Answer

Unequal pupils or unequal tracking can point to a medical condition or injury rather than impairment.

Question 5

In the HGN test, how many clues indicate a likely BAC of 0.08 or higher?

Accepted Answer

4 or more

Answer

NHTSA validation research shows that four or more of the six clues indicates a probable BAC of 0.08 or above.

TCOLE - Texas Commission on Law Enforcement Practice Test