Page 41 - Argyle Police Officer Field Training Tips

DWI Investigations

When is this positioning used? This is used in situations where an officer has pulled over a vehicle and
the driver is suspected of DWI. Remember, this is just one way of doing things. Officers are represented
by the blue dots.

HGN

When doing HGN face the subject away from the vehicle. Preferably as
close to the shoulder as possible while assuring they are on level
ground to minimize their chances of falling and still within the view of
the in car camera. I like this area.

1. Set up your front dashboard camera towards the area you plan

to be handing the DWI investigation.
2. Turn off your patrol front facing lights (red and blues)
3. Ask initial questions such as: Have you ever had any TBI’s or

past head trauma? Do you wear lenses for corrective vision?
Do you have any leg or joint issues which would prevent you
from taking these tests? Are you under the influence of any

medications?
4. Have a stimulus ready. You can use a pen, a pen light, or your
finger (as a last resort). I prefer to use a green tipped light pen

so there’s no confusion to a blue or red light. And make sure
the actor verifies the color of the pen light so it cannot be
argued they did not recognize the stimulus.

Pg. 40 POLICE FIELD TRAINING CONCEPTS