Policy Text
MOUNTAIN VIEW POLICE DEPARTMENT
SPECIAL SERVICES SECTION
TRAINING AND INFORMATION
BULLETIN
PAGE 1 OF 1
2023
DATE: October 31, 2023
BULLETIN NUMBER: 23 - 11
SUBJECT: PD-94, Influence Investigation Report
INFORMATION:
The PD-94, Influence Investigation Report, is a tool to help focu s and standardize your DUI and
HS 11550 investigations. If you are doing an alco hol only related DUI investigation or a HS
11550 investigation without driving involved, you do not need to fill out every box on the form.
If the subject is too intoxicated to safely perfor m the tests or otherwise unable to perform the
tests, you do not need to go through every test to make a determinati on. However, since polydrug
(including alcohol) use is so prevalent when pe rforming a DUI investigat ion best practice would
be to include every test on the form. National Highway Traffic Safety Administrati on (NHTSA) has developed three standardized
field sobriety tests (SFST); Nystagmus, Walk an d Turn, and Leg Raise. These tests must be
explained and performed in a manner consistent with how the tests were conducted during the
SFST validation studies. The PD-94 form instructions are consiste nt with the validation studies.
This allows you to testify to their validity in court. If you perform the tests outside of the
guidelines, it is much easier for the test to be thrown out of court.
If only alcohol intoxication is suspected, it is ac ceptable and recommended to perform only these
three SFST. However, it is difficu lt to properly identify drug in fluence without a complete DAR
examination and by focusing solely on the SFST, o fficers may not be gett ing a complete picture
of the driver’s intoxication. Especial ly if the driver is below .08 BAC.
The Standing Balance (AKA; Rhomberg) and Fi nger to Nose are not validated SFST. The
Standing Balance exercise is th e only exercise used during a DAR examination where DUI is not
involved. The Finger to Nose test is useful in helping office rs make a determination when
subjects claim injuries or other issues that will not allow them to perform the Walk and Turn or
Leg Raise. Both Standing Balan ce and Finger to Nose, while not va lidated, can be used to make
a probable cause determination for arrest. Using all five tests when su specting drug and alcohol
use will only give you more info rmation on the level and category of the driver’s impairment.
Prepared by: Lt. St.Clair Approved by: Capt. Magee