There are several DUI tests that an officer administers while detaining a person on suspicion of DUI. These tests are known as Field Sobriety Tests (FSTs). The FSTs are “standardized” or “non-standardized."

​FSTs are optional. This means that the driver does not have to comply with the officer's request that the driver submit to the FSTs; However, the arresting officer is not under an obligation to inform the driver that FSTs are optional. Caution: If you refuse to take a BAC test, you will automatically lose your license for at least a year. BAC tests are different than FSTs. BAC tests are the chemical tests such as the breathalyzer, blood, or urine test used to determine the driver's Blood Alcohol Level. California law grants a privilege to drive based on the defendant's implied consent to take a BAC test upon an officer's request.

​A San Bernardino DUI Attorney will review the arrest record in search of improper administration of the FST tests. If the arresting officer did not properly administer the tests than the evidence of the results of the driver's FSTs should be suppressed (unusable by the district attorney) or at least impeached (discredited). Some of the laws for the proper administration of the FST tests are found at Title 17 of the California Code of Regulations.

​Standardized FSTs include:

​Nystagmus Test: This DUI test is administered by having the driver follow an object with his or her eyes without moving their head. Usually the officer holds a pen or some other small object out in front of the driver about a foot from the driver's head. The officer is looking to see if the driver moves his head instead of his eyes which might indicate intoxication. But more importantly, the officer is checking to see if the driver's eyes are bouncing around or “floating” within the eye socket. This might indicate intoxication.

​"Walk and Turn" Test: This DUI test is administered by having the driver take a certain amount of steps forward and backward with the heel to toe for each step. The officer is looking for imbalance or lack of following instruction as a reason to suspect the driver is DUI.

​Rhomberg Balance Test: This DUI test is administered by having the driver take a position of attention, close his or her eyes, tilt his or her head back, and estimate 30 seconds. The officer is looking for bad balance to indicate intoxication or bad time estimation as evidence of stimulants or depressants.

​Other FSTs include non-standardized FSTs, such as having the driver tap certain fingers together, count backwards, recite ABCs backwards, etc. The list below was developed by the National Highway Transportation Safety Association (NHTSA) to assist officers detect DUI and are considered other non-standardized tests:

​Turning with wide radius

​Driver appearing drunk

​Driver straddling the center divider

​​Weaving or driving off the road

​Driving more than 10 miles under limit

​​​Driving with no headlights

​Rapid acceleration or deceleration

​Inappropriate stopping or braking

​Wrong signaling & Abrupt Turns

​​​Drifting, tailgating, or swerving

​Stopping in the middle of the road

​Slow response to traffic signals

​Notice that speeding is not a DUI detection indicator according to the NHTSA.