First phase of DUI detection.
Vehicle in motion.
Second phase of DUI detection.
Personal contact.
Third phase of DUI detection.
Pre-arrest screening.
BAC vs BrAC
Blood alcohol concentration vs breath alcohol concentration
Nystagmus
Involuntary jerking of the eyes
Probable cause
Facts and circumstances leading an officer to believe an offense has been or is being committed.
Reasonable suspicion
Less than probable cause but with reasonable belief and articulation that a crime is taking or has taken or is about to take place.
When did NHTSA first do field studies and where.
California 1975
Colorado field study date
1995
Florida field study date
1997
San Diego field study date
1998
Colorado field study 3 test battery correct arrest decision rate
86%
Florida field study 3 test battery correct arrest decision rate
95%
San Diego field study 3 test battery correct arrest decision rate
91%
San Diego field study HGN TEST ONLY correct arrest decision rate
88% accurate
San Diego field study WAT TEST ONLY correct arrest decision rate
79% accurate
San Diego field study OLS TEST ONLY correct arrest decision rate
83% accurate
