Can You Refuse a Field Sobriety Test? Field, Breath and Blood Tests Compared

Can you refuse a field sobriety test? In many states, yes: roadside tests like walking a line or standing on one leg are voluntary, and refusing them carries no penalty of its own, though the officer can still arrest you based on other signs. Breath and blood tests after an arrest are different. Every state has an implied consent law, so refusing an evidential test usually brings a license suspension and can be used against you in court.

Test	When it's asked	Can you refuse?	What refusing usually means
Roadside field sobriety tests (eye test, walk-and-turn, one-leg stand)	During the stop, before arrest	Usually yes	No separate penalty in many states; the officer may still arrest you
Preliminary breath test on a handheld device	During the stop	Depends on the state	A fine or citation in some states; nothing in others
Evidential breath test	After arrest	You can refuse, with consequences	License suspension under implied consent; refusal can be evidence
Blood test	After arrest	Police generally need a warrant	You can't be criminally punished for refusing a warrantless blood test

The breath and blood rules come from Birchfield v. North Dakota (2016): the Fourth Amendment allows warrantless breath tests incident to a drunk-driving arrest but not warrantless blood tests, and drivers can't be criminally punished for refusing a blood test based on implied consent. We read the decision on November 7, 2026. Civil penalties, like license suspension, can still apply.

Why people refuse roadside tests

Field sobriety tests are judged by the officer, and things unrelated to alcohol can affect them: nerves, footwear, an injury, the road surface, age or weight. Refusing doesn't prevent an arrest, but it means the officer has less evidence from the stop. Whether to take them is your decision at the scene; a lawyer can't make it for you after the fact.

What refusing an evidential test costs

Under implied consent laws, by driving you're treated as agreeing to an evidential breath or blood test after a lawful arrest. Refusing usually means:

• an automatic license suspension, often longer than for a failed test;
• the refusal may be used as evidence at trial in many states;
• in some states, refusing a breath test after arrest is a crime of its own, which Birchfield allows for breath tests.

Commercial drivers face stricter rules, including a 0.04% alcohol limit on duty (49 CFR § 382.201).

At the stop

1. Stay calm and give your license, registration and insurance when asked.
2. You can decline to answer questions about drinking.
3. Ask whether a test is required or voluntary.
4. If arrested, ask what happens if you refuse the evidential test before deciding.
5. Write down everything afterward, and note the deadline to challenge a suspension. For costs, see DUI lawyer cost.