DWI Field Sobriety Tests (SFSTs) have 99 Problems . . .Texas DWI and Field Sobriety Test Lawyers

. . . but, courtroom admissibility ain’t one.

Despite many issues with outdated field sobriety exerices, they continue to form the basis for DWI arrests and subsequent prosecutions.


  1. Hired Guns: Many DWIs involve special DWI tasks force. Hired guns looking for and expecting to make DWI arrests.
  2. Officer Street Bias: (see 1) It’s 3 a.m., you knicked a curb. Officer’s are looking for DWIs. You gotta be DWI.
  3. Time & 1/2 : the officer receives time & a ½ to come testify in court. Aggressive DWI lawyers routinely contest the officer’s opinion you were intoxicated. DWI trials = officer bonuses.
  4. Subjective: The decision to arrest a person for DWI is based on the subjective opinion & bias of the officer.
  5. Political Influence: The day Mothers Against Drunk Driving was formed, is the day DWI laws changed forever. A DWI arrest alone can result in driver’s license suspensions, interlock devices, random urine tests, etc.
  6. Probable Cause: All that is needed for an officer to make an arrest. A crime may have been committed. It is a low burden. Significantly lower than proof beyond a reasonable doubt.
  7. Presumption of Guilt: trained officers have made an arrest, so they must be guilty???
  8. Exercises designed to make arrests, not to prove intoxication. The Standardized Field Sobriety Tests were implemented to assist in arrests, not to prove DWI beyond a reasonable doubt.
  9. Coordination Exercises designed to fail: you are not told what signs of intoxication the officer is looking for on the field sobriety tests and do not get credit for the things you do well.
  10. Exercises place a person in abnormal situations. How often do you stand with your one foot directly in front of the other? How often are you balancing on one foot?
  11. “You don’t know me, man”: The officer is meeting you for the first time: Under the law, the definition of intoxication includes not having the normal use of your mental or physical faculties. The problem is the officer has no idea what is normal for you.
  12. What is Normal? Normal for you, is not normal for me. Normal for Lebron James is not normal for me (or I wouldn’t be writing this).
  13. Isn’t an abnormal reaction to an abnormal situation normal? (see 10)
  14. Sleep Deprivation: can mimic signs of intoxication.
  15. Diabetes: can mimic signs of intoxication.
  16. Head injuries: can mimic signs of intoxication.
  17. Officer’s often fail to inquire into a person’s medical history (despite their training and instructions)
  18. Nervousness can mimic signs of intoxication. Ever seen a professional golfer miss a 1 ft. putt? A gymnast miss the landing? Routines they have perfected and practiced thousands of times. Why? Nerves.
  19. 1977 “Psychophysical Tests for DWI Arrest”: used in the development of field sobriety exercises. Narrowed 6 tests down to 3 (tAlcohol Gaze Nystagmus, Walk & Turn & One Leg Stand) while noting the tests “yield more precise results . . . in the station.”This study had a 47% false arrest error rate: Officer’s were wrong nearly ½ the time…in controlled environments.
  20. 1981 “Development and Field Test of Psychophysical Test For DWI Arrests”: Expanded on the 3 field sobriety exercises and recommended an 18-month field evaluation.
  21. The 18-month field evaluation was never completed.
  22. But a 3-month field evaluation was in the 1983 study “Field Evaluation of a Behavioral Test Battery for DWI.” This evaluation required officers to administer field sobriety exercises to any person they suspected of DWI. This study was based on the Honor system, without researchers riding along to see if the tests were being administered correctly.
  23. Zero of these “studies” have been submitted for peer review.
  24. Zero of these “studies” have ever been published in any scientific journals.
  25. No control group existed to evaluate a non-drinker or sober person’s performance on the exercises.
  26. Shouldn’t the expert officer know the studies, the instructions, and the clues like the back of their hand? In court testimony often reveals just the opposite.
  27. The Colorado Study: 1 out of every 8 participants failed the Horizontal Gaze Nystamus test although having a BAC under 0.05.
  28. The Florida Study: 67% of all incorrect arrests had maximum clues on the Horizontal Gaze Nystagmus Test; 70% of subjects under 0.08 failed the Walk & Turn.
  29. The San Diego Study: subjects under 0.08 were wrongfully arrested at a rate 6Xs more than those with a BAC over 0.08; 37% of subjects under 0.08 failed the HGN; 52% of subjects under 0.08 failed the walk and turn; and, 41% of subjects under 0.08 failed the one leg stand.
  30. The Robustness Study: This study looked at minor deviations on the Horizontal Gaze Nystagmus (HGN) and the impact on determining impairment. An average false positive rate of 66.7% (76.9%, 54.1%, 69.2%) was reported.
  31. Jim Booker’s peer-reviewed study, End Position Indicator of Ethanol Intoxication (Science and Justice 2001; 41: 113-116) finding alarming problems with the Nystagmus test, including:
  32. 19% of subjects had nystagmus before consuming any alcohol;
  33. 62% had nystagmus after reaching 0.00;
  34. 56% had nystagmus an hour after reaching 0.00;
  35. 37% people during absorption had nystagmus between 0.01 – 0.05;
  36. During elimination, 68% had nystagmus between 0.01 – 0.05.
  37. Not-Standardized? Non-standardized tests are often administered by the officer, like the Rhomberg test, also used to detect venereal disease.
  38. Science? The National Highway and Safety Administration thinks so, many disagree.
  39. Or Junk-Science: try to balance on one leg for 30 seconds and see how you do.
  40. Show me the evidence? What happen to the on-scene video?
  41. Mic Check? There is a video, but where did the sound go? Why does the officer turn his mic on and off?
  42. Horizontal Gaze Nystagmus: Flashing Lights can cause nystagmus
  43. Head Injuries can cause nystagmus
  44. Medical Conditions can cause nystagmus
  45. Eye Injuries can cause nystagmus
  46. Nicotine can cause nystagmus
  47. Caffeine can cause nystagmus
  48. Natural Nystagmus & Resting Nystagmus: some (unknowingly) have natural nystagmus.
  49. There are all types of Nystagmus
  50. And the officer can’t tell the difference.
  51. Test is Depressant specific, not alcohol specific: there are a lot of depressants other than alcohol.
  52. Equal Tracking? Did the officer check to see if the eyes tracked equally?
  53. Equal Pupil Size? Did the officer check the subject’s pupil size?
  54. Dust can interfere with the test
  55. Wind can interfere with the test
  56. Officer holds stimulus too high – test invalid
  57. Officer holds stiumulus too low – test invalid
  58. Officer takes stimulus out too far – test invalid
  59. Officer moves stimulus too slow – test invalid
  60. Officer moves stimulus too fast – test invalid
  61. Stimulus held out too long – test invalid
  62. Stimulus held out not long enough – test invalid
  63. Incorrect # of passes – test invalid
  64. 82 seconds should be the minimum time it takes for the officer to perform the HGN.
  65. Rubber Stamp: rarely do the officers not “find” 6 of 6 clues (or a strong odor of alcohol on your breath and red, blood shot glassy eyes).
  66. What do the eyes look like? The officer can see the nystagmus (bouncing of the eyes), but no one else can.
  67. Vertical GazeNystagmus: inadmissible and not standardized.
  68. Walk and Turn and One Leg Stand: Incorrect Instructions – test invalid.
  69. Officer distractions on the Walk & Turn and One Leg Stand can impact the subject’s performance. The officer should be quiet. The officer should be still.
  70. Passing traffic can impact the subject’s performance.
  71. The Walk and Turn Test and the One Leg Stand should not be conducted on a slippery, wet, or un-level surfaces.
  72. Failing before you even start: the first two signs of intoxication on the Walk and Turn test are starts too soon and can’t balance during instructions. Two strikes and you’re out, meaning you can fail this test before you ever walk the line.
  73. C = F: if you get 6 of 8 clues correct (75%) on the walk and turn you still fail.
  74. What you don’t know will kill you: the officer doesn’t tell you what signs of intoxication or clues he is looking for.
  75. Uses arms for balance is a clue. This means raising both arms more than 6”. You are not told this.
  76. Steps off-line is a clue. This means one foot comes entirely off the line. You are not told this.
  77. Heel-to-toe is a clue. You get a 1/2″. You are not told this.
  78. Improper Turn is a clue. If you remove your front foot from the line while turning, you get docked.
  79. Stops while walking is a clue. This should only be marked if you pause for several seconds.
  80. During the One Leg Stand officer’s often tell subjects to pick their foot up if they put it down. That is not an instruction. Officer’s often tell subjects to point their toes, this is not an instruction.
  81. Test too long or too short? Officer should discontinue the One Leg Stand at 30 seconds
  82. Failing: 4 total clues. 2 strikes and you’re out.
  83. Using arms for Balance is a clue (6+”). Aren’t we taught to balance with our arms out as kids?
  84. Swaying back and forth or side to side is a clue. Who wouldn’t sway on one foot?
  85. Age can impact performance.
  86. Back & Leg Injuries can impact performance.
  87. Inner ear problems can impact performance.
  88. Your shoes can impact performance and you should be allowed an opportunity to remove them.
  89. Inadequate Training: one week course is all it takes to become an expert.
  90. Signs of Sobriety? They often outweigh the signs of intoxication.
  91. Consistently Inconsistent: When a person does well on the tests, officer’s say their decision to arrest for DWI was based on the “totality of the circumstances.”
  92. Form Police/Offense Reports: district attorney offices provide easy fill in the blank forms which feed the necessary signs of intoxication and field sobriety clues.
  93. Accused 1st time: The subject doesn’t know what to expect on the test.
  94. Officer’s 100th+ time demonstrating the test. Practice makes perfect.
  95. Refuse and be arrested: Your refusal will be taken as a sign of hiding intoxication.
  96. Perform and be arrested: the officer’s mind was made up at “have you been drinking.”
  97. Mi—randa? The officer will say you were not under arrest, so Miranda doesn’t apply. What you say will be used against you.
  98. The Calvary: other officers (a.k.a. friends, colleagues, supervisors) on the scene will bolster each other’s opinion and testimony as to your intoxication.
  99. Validity Compromised: Despite the officer’s training manual stating, “if any one of the standardized field sobriety test elements is changed, the validity is compromised”, Texas courts continue to find creative ways to allow improperly administered field sobriety exericises into evidence. The Texas Court of Appeals in Compton v. State concluded “slight variations” do not render the tests inadmissible. As such the DWI criminal lawyer must highlight all the normal and sober signs their client exhibited, while pointing out the inherent bias of these unforgiving and outdated exercises and trusting the jury to follow the law in reaching their final vedict.