When police suspect someone of drunk driving, they will normally ask the person to perfect certain tests. DUI testing generally falls into one of two categories: field sobriety tests (FSTs) and chemical testing.
Generally, police use FSTs to get a better idea of whether a driver is under the influence of drugs or alcohol. There are three "standardized FSTs" that police often administer during DUI investigations. Studies have been done that purportedly showed these standardized tests are reliable for gauging intoxication. The standardized FSTs are called the "horizontal gaze nystagmus test," "one-leg-stand test," and "walk-and-turn test." As a general rule (and unlike with chemical testing), there is no legal penalty for refusing to take an FST.
In most cases, if an officer has probable cause to believe that you are driving under the influence, “implied consent laws” require you to take a chemical test (using your blood, breath, or urine) to determine your blood alcohol content (BAC). Implied consent laws say that by just driving on the road, you are agreeing to take a chemical test to assess your BAC. Implied consent laws vary by state—particularly with regard to which test is required—but every state has them.
In some states, a chemical test must be given within a particular timeframe—usually within a few hours of the time that you were driving. However, even if you took the test after that time, you could still be found guilty of a DUI. To prove a DUI, the prosecution can either prove a BAC of .08% or more (less for underage drivers) or actually driver impairment. So, a BAC test isn't absolutely necessary for a DUI conviction.
Drivers who unlawfully refuse to take the test face serious consequences—normally, worse than if you were just found guilty of driving under the influence. Depending on the circumstances, a refusal can lead to license suspension, jail time, fines, and having to install an ignition interlock device (IID). Additionally, if your case goes to trial, the prosecution can typically use your refusal against you—arguing that you knew you were intoxicated and that’s why you refused to take the test.
| State | 1st Offense | 2nd Offense | 3rd Offense |
|---|---|---|---|
| Alabama | 90-day suspension | 1-year suspension | 1-year suspension |
| Alaska |
3 days jail; mandatory IID; fines up to $1,500 (jail can't be imposed for refusal to submit to a warrantless blood test) |
20 days jail; mandatory IID; fines up to $3,000 (jail can't be imposed for refusal to submit to a warrantless blood test) | 60 days jail; mandatory IID; fines up to $4,000 (jail can't be imposed for refusal to submit to a warrantless blood test) |
| Arizona | 1-year suspension | 2-year suspension | 2-year suspension |
| Arkansas | 6-month revocation | 2-year revocation | 3-year revocation |
| California | 1-year suspension | 2-year suspension | 3-year suspension |
| Colorado | 1-year revocation | 2-year revocation | 3-year revocation |
| Connecticut | 1-year suspension | 2-year suspension | 3-year suspension |
| Delaware | 1-year revocation (2 years if under 21 years of age) | 1-year revocation (2 years if under 21 years of age) | 1-year revocation (2 years if under 21 years of age) |
| District of Columbia | 1-year suspension | 1-year suspension | 1-year suspension |
| Florida | 1-year suspension | 18-month suspension | 18-month suspension |
| Georgia | 1-year suspension | 3-year suspension | 5-year suspension |
| Hawaii | 1-year revocation | 2-year revocation | 4-year revocation |
| Idaho | 1-year suspension; $250 fine (however, defendants who install an IID on their vehicle may be eligible for a restricted license that allows for driving to/from work/school) | 2-year suspension; $250 fine (however, defendants who install an IID on their vehicle may be eligible for a restricted license that allows for driving to/from work/school) | 2-year suspension; $250 fine (however, defendants who install an IID on their vehicle may be eligible for a restricted license that allows for driving to/from work/school) |
| Illinois | 1-year suspension | 3-year suspension | 3-year suspension |
| Indiana | 1-year suspension | 2-year suspension | 2-year suspension |
| Iowa | 1-year revocation | 2-year revocation | 2-year revocation |
| Kansas | 1-year suspension | 2-year suspension | 3-year suspension |
| Kentucky | Minimum 30-day revocation | Minimum 1-year revocation | Minimum 2-year revocation |
| Louisiana | 6-month revocation | 6-month revocation | 2-day minimum jail term |
| Maine | 275-day suspension | 18-month suspension | 4-year suspension |
| Maryland | 120-day suspension | 1-year suspension | 1-year suspension |
| Massachusetts | 180-day suspension | 3-year suspension | 5-year suspension |
| Michigan | 1-year suspension | 2-year suspension | 5-year suspension |
| Minnesota | 1-year revocation of license | 1-year revocation of license | 1-year revocation of license |
| Mississippi | 90-day suspension | If first offense was a DUI: 1-year suspension. If first offense was a refusal to take test: 90-day suspension | If the first or second offense was a DUI: 1-year suspension |
| Missouri | 1-year revocation | 1-year revocation; IID must be installed | 1-year revocation; IID must be installed |
| Montana | 6-month suspension | 1-year suspension | 1-year suspenion |
| Nebraska | 90-day license impounded | 90-day license impounded | 90-day license impounded |
| Nevada | 1-year suspension | 3-year suspension | 3-year suspension |
| New Hampshire | 180-day suspension | 2-year suspension | 2-year suspension |
| New Jersey | 7-month revocation | 2-year revocation | 10-year revocation |
| New Mexico | 1-year revocation | 1-year revocation | 1-year revocation |
| New York | 1-year suspension | 18-month suspension | 18-month suspension |
| North Carolina | 1-year suspension | 1-year suspension | 1-year suspension |
| North Dakota | 1-year revocation | 3-year revocation | 4-year revocation |
| Ohio | 1-year suspension | 2-year suspension | 3-year suspension |
| Oklahoma | 6-month revocation | 1-year revocation | 3-year revocation |
| Oregon | 1-year suspension | 3-year suspension | 3-year suspension |
| Pennsylvania | 1-year suspension | 18-month suspension | 18-month suspension |
| Rhode Island | 6-month suspension | 1-year suspension | 2 to 5-year suspension |
| South Carolina | 6-month suspension | 9-month suspension | 1-year suspension |
| South Dakota | 1-year revocation | 1-year revocation | 1-year revocation |
| Tennessee | 1-year revocation | 2-year revocation | 2-year revocation |
| Texas | 180-day suspension | 2-year suspension | 2-year suspension |
| Utah | 18-month suspension | 3-year suspension | 3-year suspension |
| Vermont | 6-month suspension | 18-month suspension | Lifetime license suspension |
| Virginia | 1-year suspension | 3-year suspension | 3-year suspension |
| Washington | 1-year suspension | 2-year suspension | 3-year suspension |
| West Virginia | 1-year | 10-year revocation | Lifetime license revocation |
| Wisconsin | 1-year revocation | 2-year revocation | 3-year revocation |
| Wyoming | 6-month suspension | 18-month suspension | 18-month suspension |