# Should a sober person take a field sobriety test? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [July 19, 2022, 2:06pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204 "2022-07-19T14:06:00Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [July 19, 2022, 4:12pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/21 "2022-07-19T16:12:01Z")
So do you see any upside to “offering” to take one if you have not yet been asked to? ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [July 19, 2022, 4:14pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/22 "2022-07-19T16:14:26Z")
> [@xizor](#): > > This is kind of what happened to me. I was taken to the local jail intake (that was where the breathalyzer was) and blew well under the legal limit. > Then they said you are free to go. Great, my car was about 5 miles away on the side of the road. This being the days before Uber and smart phones, and I had no cash for a taxi, I got to walk back to my car in the middle of the night. 😡 Is there really no law against the cops doing this? Or would it be something they could weasel out of by saying “we can take you, but we just got an urgent call so you may have to wait 3 hours”. ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 4:18pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/23 "2022-07-19T16:18:16Z")
> [@Riemann](#): > > So do you see any upside to “offering” to take one if you have not yet been asked to? At the roadside, cops sometimes have “pbt’s” - portable breath tests - which are not admissible in court, but can be used to verify a hunch that somebody is not impaired. If you’re sober, and cops are investigating you for a DUI, you could offer to take a PBT to show them. Otherwise, admissible breath results come from calibrated machines when following certain procedures (e.g. there is supposed to be a 20 minute observation period before you test, during which you are not to regurgitate, drink water, or put anything in your mouth). I’ve seen these tests done at the roadside (the machine may be in the back of a car), but they are usually done down at the station. You can’t “volunteer” to do one of those, but will be told to do it if you are arrested, with the understanding that your license will be suspended if you refuse. So, post arrest (and not impaired)? Yeah, I’d blow. Before arrest, tell them you aren’t impaired and ask for a portable test. But if they still think impairment, they might arrest you on suspicion of drug intoxication and then request a urine sample/conduct a drug evaluation. ---
**Author:** ![Jingleheimer-Schmidt](https://avatars.discourse-cdn.com/v4/letter/j/eb8c5e/32.png) [@Jingleheimer-Schmidt](https://boards.straightdope.com/u/Jingleheimer-Schmidt)\ **Post date:** [July 19, 2022, 4:19pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/24 "2022-07-19T16:19:45Z")
> [@Moriarty](#): > > So, the cop needs probable cause to believe you are DUI, therefore justifying an arrest, at which time you are deemed to have “consented” to provide the breath sample by virtue of having obtained a driver’s license (check yours. There’s likely some notation about consenting to a breathalyzer when legally required). A cop’s probable cause for requiring a breathalizer test is going to be even more subjective than a FST, and I doubt if that requirement will prevent any cops from administering these tests, ever. My understanding - which could be wrong and/or vary by state - is that people can technically not be forced to take breathalizer tests, but that refusal to take them is grounds for license suspension. Which is sort-of consistent with what you write, in that the consent is a function of the licensing system, but not so in that it’s not a true legal consent which just happens to appear on a license. ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 4:23pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/25 "2022-07-19T16:23:12Z")
> [@Jingleheimer-Schmidt](#): > > My understanding - which could be wrong and/or vary by state - is that people can technically not be forced to take breathalizer tests, but that refusal to take them is grounds for license suspension. Yes, precisely. It’s a choice, but one with consequences, based on the idea (called implied or express consent, depending on the jurisdiction) that you agreed to this when you got your license. (Interestingly, at least in Florida, this consent is the default presumption. So, if you are unconscious following a DUI arrest - say, because you were in an accident, or just really plastered - you’ve already consented to have your blood drawn to test for alcohol; a blood draw being acceptable if a breath or urine test is “impossible or impractical”) ---
**Author:** ![Jingleheimer-Schmidt](https://avatars.discourse-cdn.com/v4/letter/j/eb8c5e/32.png) [@Jingleheimer-Schmidt](https://boards.straightdope.com/u/Jingleheimer-Schmidt)\ **Post date:** [July 19, 2022, 4:49pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/26 "2022-07-19T16:49:35Z")
> [@Moriarty](#): > > It’s a choice, but one with consequences, based on the idea (called implied or express consent, depending on the jurisdiction) that you agreed to this when you got your license. I had thought that - based on the notion that “driving is a privilege and not a right” - that anything where the only consequence is license suspension is not legally coercion. Based on what you say, it would seem that if the government instituted some sort of **new** test where the (only) consequence for refusal was license suspension, that this would be legally problematic, because since it was not in place at the time people got their licenses there is no implied or express consent for it. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [July 19, 2022, 4:55pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/27 "2022-07-19T16:55:46Z")
IANAL. If this is a “need answer now” situation consult an attorney I don’t know if YMMV depending on the state or if it based on federal law, but @Moriarty absolutely nailed Colorado case law. Also they cannot make you do a FST without already having probable cause but they can make you get out of your car and walk to the back in the interest of officer safety (People v Carlson). As for field breathalyzer, they are not covered under Colorado’s implied consent law IF you are 21+ and you cannot be punished by the DMV for refusing it. You will have your license suspended if you refuse the tests after arrest. > ## 4. What happens if the police suspect DUI? > > If officers suspect DUI, they can ask the driver to **step out** of the vehicle. Then they can ask the driver to take the following tests: > > - [Field sobriety tests (FSTs)](https://www.shouselaw.com/co/dui/field-sobriety-tests/), and/or > - [Preliminary alcohol screening (“PAS”) breath test](https://www.shouselaw.com/co/dui/laws/preliminary-breath-tests/) > > The FSTs and PAS breath tests are **optional**. Suspects may decline to take them without legal consequences. > > If suspects _do_ take them, the FST results can come into court as evidence of impairment. For drivers 21 or over, PAS results are admissible to prove the officers had probable cause. (People under 21 facing only a UDD charge must take the roadside breath test.) > > Officers that believe a suspect is intoxicated may **arrest** him/her for either: > > - Driving under the influence of alcohol (DUI) or driving under the influence of drugs (DUID) – [42-4-1301 (1)(a), C.R.S](https://www.shouselaw.com/co/dui/crs42-4-1301/).; > - [DUI “per se” (driving with a BAC of .08% or higher) – 42-4-13-1 (2)(a), C.R.S.](https://www.shouselaw.com/co/dui/laws/dui-per-se/); > - Driving while ability impaired (DWAI) by alcohol and/or drugs – 42-4-1301 (1)(b), C.R.S.; or > - [Underage drinking and driving (UDD) – 42-4-1301 (2)(d)(I), C.R.S.](https://www.shouselaw.com/co/dui/laws/under-21/) > > Upon arrest, the driver must take an evidentiary breath alcohol test (EBAT) or blood test. Normally, arrestees are allowed to choose which test. But if the police suspect drug use, the arrestee must take a blood, urine, or saliva test. > > Refusing to take a **chemical test** after an arrest has consequences. Two include: > > 1. Automatic [revocation of the Colorado driver’s license](https://www.shouselaw.com/co/dui/laws/license-suspension/), and > 2. Designation as a [Colorado “persistent drunk driver”](https://www.shouselaw.com/co/dui/laws/persistent-drunk-drivers/) (even if it is the first arrest) > > Also, the refusal can be used as **evidence of guilt** if the case goes to trial. [From here](https://www.shouselaw.com/co/dui/checkpoints/). ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [July 19, 2022, 5:13pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/28 "2022-07-19T17:13:12Z")
> [@Jingleheimer-Schmidt](#): > > My understanding - which could be wrong and/or vary by state - is that people can technically not be forced to take breathalizer tests, but that refusal to take them is grounds for license suspension. > [@Moriarty](#): > > Yes, precisely. It’s a choice, but one with consequences, based on the idea (called implied or express consent, depending on the jurisdiction) that you agreed to this when you got your license. > [@Saint\_Cad](#): > > I don’t know if YMMV depending on the state or if it based on federal law, but @Moriarty absolutely nailed Colorado case law. This is quite confusing, since what @Moriarty said is actually contradicted by @Saint_Cad 's subsequent quote. I think we are getting muddled between the roadside breathalyzer and the evidentiary test? Is this a correct summary? - You are under no obligation to take the Field Sobriety Test (FST), and there is little upside in doing so since it is so subjective that it is unlikely to “clear” you immediately, and far more likely to provide additional probable cause. - The roadside breathalyzer (PAS) is also only administered pre-arrest (?), it is also optional, it is not valid as evidence, and refusing it has no direct legal consequences. But volunteering to take it if you know you are sober could certainly save you some time, since it is more objective than the FST and could clear you immediately in the eyes of law enforcement (but may not if they suspect other drug use). - If you are arrested, you will be taken to the station, where a more rigorous evidentiary test will be administered. You cannot refuse this (or if you do, you may lose your license and suffer other consequences as a direct result). This may be either a breath test or a blood test. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [July 19, 2022, 5:28pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/29 "2022-07-19T17:28:19Z")
> [@Riemann](#): > > This is quite confusing, since what @Moriarty said is actually contradicted by @Saint_Cad 's subsequent quote. Yes and no. > [@Riemann](#): > > I think we are getting muddled between the roadside breathalyzer and the evidentiary test? Exactly. There is no “the” breathalyzer test so @Moriarty was right in regards to the breathalyzer test (or blood test) down at the station but not if he was referring to the field test. I thought he was referring to the first one only since he said > Otherwise, admissible breath results come from calibrated machines when following certain procedures (e.g. there is supposed to be a 20 minute observation period before you test, during which you are not to regurgitate, drink water, or put anything in your mouth). I’ve seen these tests done at the roadside (the machine may be in the back of a car), but they are usually done down at the station. > > You can’t “volunteer” to do one of those, but will be told to do it if you are arrested, with the understanding that your license will be suspended if you refuse… ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [July 19, 2022, 5:30pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/30 "2022-07-19T17:30:26Z")
> [@Saint\_Cad](#): > > There is no “the” breathalyzer test so @Moriarty was right in regards to the breathalyzer test (or blood test) down at the station You’re right, this is the source of confusion (or at least _my_ confusion). To me the term “breathalyzer” means specifically the hand-held machine that administers the roadside test - for which I gather the correct technical term is “PAS”, right? ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 5:34pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/31 "2022-07-19T17:34:22Z")
> [@Saint\_Cad](#): > > @Moriarty absolutely nailed Colorado case law. Well, it is one of two states where I am licensed to practice. DUI law is generally applied, anyway. > [@Riemann](#): > > You are under no obligation to take the Field Sobriety Test (FST), and there is little upside in doing so since it is so subjective that it is unlikely to “clear” you immediately, and far more likely to provide additional probable cause. Correct. > [@Riemann](#): > > The roadside breathalyzer (PAS) is also only administered pre-arrest (?), it is also optional, it is not valid as evidence, and refusing it has no direct legal consequences. But volunteering to take it if you know you are sober could certainly save you some time, since it is more objective than the FST and could clear you immediately in the eyes of law enforcement (but may not if they suspect other drug use). Correct, except not all cops will have a PBT or ever use one. > [@Riemann](#): > > If you are arrested, you will be taken to the station, where a more rigorous evidentiary test will be administered. You cannot refuse this (or if you do, you may lose your license and suffer other consequences as a direct result). This may be either a breath test or a blood test. Correct, with these caveats: The test is usually breath or urine. Blood is considered more invasive, and so usually requires some aggravating factor (like serious bodily injury or death of somebody involved) before it can be requested without a warrant. Also, the refusal, or if you blow above a .08, will result in a suspension, but you do usually have a chance to challenge this at an administrative hearing conducted by the DMV. It’s not a criminal matter, but an administrative one, so you’ll be held to a lower evidentiary standard, and the hearing officer will usually be a quasi prosecutor, so the deck is really stacked against you. Occasionally, though, the officer doesn’t show, or admits to a mistake, and so you might win. Even if you win, though, it just means that the DMV doesn’t administratively suspend your license. If you’re later convicted of the DUI in the criminal case (or enter a plea), you may still face a license suspension as a court imposed sanction. ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 5:39pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/32 "2022-07-19T17:39:10Z")
> [@Riemann](#): > > To me the term “breathalyzer” means specifically the hand-held machine that administers the roadside test “Roadsides” mean the series of physical tests that cops may impose, like the “walk and turn” or “one legged stand”. These are also called Field Sobriety Tests/Exercises. These are voluntary. Do not do them. Down at the station, or via the back of a squad car, a person may be given a “breath test” using a machine called an intoxilizer - this is the breathalyzer. These are “required” if you are arrested - but you can refuse. But if you refuse (and then lose an administrative hearing where you can challenge whether the legal obligation actually arose), you face a license suspension. And, at least in Florida, if you refuse twice, it’s a misdemeanor crime. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [July 19, 2022, 5:39pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/33 "2022-07-19T17:39:33Z")
> [@Moriarty](#): > > Well, it is one of two states where I am licensed to practice. DUI law is generally applied, anyway. So if I drunk DM you here, it will probably be a “needs answer fast”. If I do a field breath test, is there any hard evidence like a receipt? They don’t hold the air for my attorney to test and what is to prevent the officer from claiming I blew a 0.11 when I’m stone cold sober? ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 5:42pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/34 "2022-07-19T17:42:07Z")
> [@Saint\_Cad](#): > > it will probably be a “needs answer fast”. Don’t say anything. But if the cops are going to arrest you, they are going to arrest you. We’ll sort it out once you bond out. ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 5:55pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/35 "2022-07-19T17:55:27Z")
> [@Saint\_Cad](#): > > If I do a field breath test, is there any hard evidence like a receipt? There is an affidavit signed by the breath test operator, along with the results from the machine and the time that they were obtained. Those results include blank samples, which are to demonstrate that the machine defaults to 0 when testing air, and references the last time the machine was calibrated (usually within a month). Also, 2 samples are taken, and if they are more than .02 apart it is considered an invalid test, and the person needs to be retested. Additionally, the test will only register with a sufficient air sample, and the person is supposed to not ingest anything, or regurgitate, for the 20 minutes prior to the test being taken. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [July 19, 2022, 5:55pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/36 "2022-07-19T17:55:29Z")
> [@Moriarty](#): > > Down at the station, or via the back of a squad car, a person may be given a “breath test” using a machine called an intoxilizer - **this is the breathalyzer**. These are “required” if you are arrested [My bold] I think there is still a confusion of terminology here. I was mistaken in my understanding of the term “breathalyzer” to _exclusively_ mean the type of small hand-held device that might be used for a pre-arrest “Preliminary Alcohol Screening”, but it certainly _includes_ these devices. And I think many people (at least where I grew up in the U.K.) would think of a hand-held device if they heard the term. > **[Breathalyzer](https://en.wikipedia.org/wiki/Breathalyzer)** > > A breathalyzer or breathalyser (a portmanteau of breath and analyzer/analyser) is a device for measuring breath alcohol content (BrAC). The name is a genericized trademark of the Breathalyzer brand name of instruments developed by inventor Robert Frank Borkenstein in the 1950s. > Research into the possibilities of using breath to test for alcohol in a person's body dates as far back as 1874, when Francis E. Anstie made the observation that small amounts of alcohol were excreted in breath. > In 1927... > In general, two types of breathalyzer are used. Small hand-held breathalyzers are not reliable enough to provide evidence in court but reliable enough to justify an arrest. **Larger breathalyzer devices found in police stations can then be used to produce court evidence.** But also, somewhat contradicting the above: > The preliminary breath test or preliminary alcohol screening test uses small hand-held breath analyzers (hand-held breathalyzers). **These units are similar to evidentiary breathalyzers, but typically are not calibrated frequently enough for evidentiary purposes.** So it seems like the only critical distinction to be aware of in whether you can refuse a test is whether you have been arrested, not the type/size of machine they are using or what they call it. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [July 19, 2022, 6:11pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/37 "2022-07-19T18:11:08Z")
Is that the field test or the later evidentiary one? I’m talking the PAS one where the cop makes you lean out the window of your car and blow just after being stopped. The one used to establish probable cause for arrest. ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 6:17pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/38 "2022-07-19T18:17:05Z")
> [@Saint\_Cad](#): > > Is that the field test or the later evidentiary one? I’m talking about the one that is used in court to establish that you were impaired (depending on the test results it may create a presumption of impairment that can’t be rebutted). That one has strict procedural standards. Any portable test that you might use while sitting in your car is not considered reliable enough to use in court. And, at least where I’ve seen it used, it’s not a basis for probable cause, either. That’s a more subjective standard based on police observations. ---
**Author:** ![Moriarty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/moriarty/32/49_2.png) [@Moriarty](https://boards.straightdope.com/u/Moriarty)\ **Post date:** [July 19, 2022, 6:36pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/39 "2022-07-19T18:36:21Z")
> [@Saint\_Cad](#): > > If I do a field breath test I missed the word “field” the last time I quoted this. If you do get a portable breath test, there won’t be results that record it. At best, you would capture it on the dash or body cameras that were recording the interaction. But, I must reiterate that portable breath tests are not universal, or even standard. Usually, you won’t be given any sort of breath test option until after you are arrested, at which time the more formal test is used. On the side of the road, cops will typically rely on more mundane factors like balance and coordination. That’s why you shouldn’t do the field sobriety tests (which is to say, physical maneuvers) that test dexterity. ---
**Author:** ![Jingleheimer-Schmidt](https://avatars.discourse-cdn.com/v4/letter/j/eb8c5e/32.png) [@Jingleheimer-Schmidt](https://boards.straightdope.com/u/Jingleheimer-Schmidt)\ **Post date:** [July 19, 2022, 7:01pm UTC](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204/40 "2022-07-19T19:01:19Z")
> [@Moriarty](#): > > But, I must reiterate that portable breath tests are not universal, or even standard. Usually, you won’t be given any sort of breath test option until after you are arrested, at which time the more formal test is used. That’s not what I’m seeing in the videos that I’ve been watching. Here’s an example of a guy being arrested immediately upon failing the handheld breathalyzer test. The guy tries to argue that he wasn’t given a choice in taking it, and the cop scoffs at him. [Live PD: Breathalyzer Is Wrong? | A&E - YouTube](https://www.youtube.com/watch?v=WiLkrw6-5js) There are others along the same lines from that same show. [Previous page](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204.md?page=1) [Next page](https://boards.straightdope.com/t/should-a-sober-person-take-a-field-sobriety-test/968204.md?page=3)