No, you generally cannot ask for a breathalyzer instead of a field sobriety test (FST) in the sense of substituting one for the other prior to an arrest. While field sobriety tests are typically voluntary, a breathalyzer or blood test usually becomes mandatory after you are lawfully placed under arrest on suspicion of driving under the influence (DUI). These two types of tests serve different purposes at different stages of a DUI investigation.
Understanding Field Sobriety Tests (FSTs)
Field sobriety tests are a series of evaluations a police officer may ask you to perform if they suspect you are impaired while driving. Their primary purpose is to help the officer determine if they have probable cause to arrest you for DUI. These tests are designed to assess your physical coordination, balance, and ability to follow instructions, which can indicate impairment.
Key points about FSTs:
- Voluntary Nature: Field sobriety tests are generally not mandatory. You have the right to decline them without immediate legal penalty directly related to the refusal of the FSTs themselves. However, refusing them might strengthen an officer's suspicion, potentially leading to an arrest if they believe probable cause exists based on other observations (e.g., erratic driving, odor of alcohol, slurred speech).
- Common Examples: Standardized FSTs often include the Horizontal Gaze Nystagmus (HGN), the Walk-and-Turn, and the One-Leg Stand.
Understanding Chemical Tests: Breathalyzers and Blood Tests
Chemical tests, such as breathalyzers administered at the police station or blood tests drawn by medical personnel, are distinct from FSTs. These tests are designed to measure your Blood Alcohol Content (BAC) or detect the presence of drugs in your system.
Key points about chemical tests:
- Post-Arrest Requirement: Unlike FSTs, if you are placed under arrest on suspicion of DUI, you are typically required to take either a breathalyzer at the police station or a blood test. You are generally not required to take both.
- Implied Consent Laws: This requirement stems from "implied consent" laws, which are in effect in all U.S. states. By driving on public roads, you are deemed to have consented to chemical testing if arrested for DUI.
- Consequences of Refusal: Refusing a chemical test after arrest can lead to severe penalties, including immediate suspension of your driver's license, even if you are not ultimately convicted of DUI. These penalties are often more stringent than those for refusing FSTs.
For more information on implied consent laws and their implications, you can refer to resources on implied consent laws related to DUI.
Key Differences: FSTs vs. Chemical Tests
It's crucial to understand the distinction between these two types of evaluations:
| Feature | Field Sobriety Tests (FSTs) | Chemical Tests (Breath/Blood) |
|---|---|---|
| Timing | Pre-arrest (to establish probable cause) | Post-arrest (to gather evidence for prosecution) |
| Voluntary? | Generally voluntary; can be declined | Mandatory after lawful arrest (due to implied consent) |
| Purpose | Assess physical/mental impairment for probable cause | Measure BAC or drug presence in your system |
| Refusal Impact | May strengthen officer's suspicion, potentially leading to arrest | Significant penalties (e.g., license suspension) and can be used as evidence of guilt |
In summary, while you have the option to decline field sobriety tests, you cannot choose to take a breathalyzer instead of performing FSTs during the initial roadside encounter. A breathalyzer or blood test typically only becomes an option, and a requirement, after an arrest has been made for suspected DUI.
