Implied Consent & Refusing a Breathalyzer
Every state has an 'implied consent' law: by driving on public roads, you've already agreed to submit to chemical testing if you're lawfully arrested for DUI. Refusing that test carries its own penalties — often harsher than the DUI itself. Here's how it works.
What implied consent means
Implied consent means that, as a condition of using public roads, you've consented in advance to a breath, blood, or urine test to measure impairment if you're lawfully arrested for driving under the influence. It's why refusing the evidentiary test triggers automatic consequences on your license.
The penalty for refusing
Refusing the required chemical test typically results in an automatic license suspension — frequently longer than the suspension for failing it — even if you're never convicted of DUI. In many states the fact that you refused can also be introduced as evidence against you in court.
Roadside test vs. the evidentiary test
There's a difference between the small handheld preliminary breath test an officer may offer at the roadside (which in many states you can decline without an implied-consent penalty) and the official evidentiary breath or blood test administered after a lawful arrest (which implied-consent laws cover). The penalties for refusal attach to that post-arrest evidentiary test.
Find your state’s penalties
Fines, jail, license suspension, and interlock rules are all set state by state — the general rules above only get you so far.
Or try the penalty estimator to filter by offense number and BAC.
Frequently asked questions
What happens if you refuse a breathalyzer?
Under implied-consent laws, refusing the official post-arrest chemical test usually means an automatic license suspension — often longer than for failing it — and, in many states, your refusal can be used as evidence against you in the DUI case.
Can you refuse a field sobriety or roadside breath test?
In many states you can decline the roadside preliminary breath test and field sobriety tests without an automatic implied-consent penalty, because those are different from the official evidentiary test given after arrest. Rules vary by state, and refusal can still affect the officer's decision to arrest.
Is refusing a breathalyzer a good idea?
It's a serious decision with real consequences that depend on your state's laws and your situation — including an automatic license suspension in most states. This is general information, not legal advice; talk to a licensed attorney about your circumstances.