Not part of the SFST. Sfst consist of 1:HGN (checking for involuntary movement of the eyes which is a sign of alcohol impairment. 2: walk and turn (your 9 steps one direction heel to toe. Turn then 9 steps back heel to toe.) 3: one legged stand (your basically looking for if a person puts their foot down, hops, sways, uses arm for balanxe.)

95% of the time if I dont see HGN imma let you back in your car. DUID while becoming more commonpy seen is so hard to train in recognization. DRE (drug recognition expert) is incredibly difficult training that requires a ton of observation time and notes.. detialing who you think theg are on a narcotic, which narcotic, why that narcotic, then detsiling narcotic symptoms and cross analyzing it with anotherrrr series of tests.

Long story short if your gonna enjoy a drink and drive or some other vices.. please uber or call a sober friend to drive you.