Alcohol, zero tolerance and implied consent

Key points

1. Alcohol and impairing drugs are involved in about 40% of fatal traffic crashes.

   Source: Handbook p. 19

   “Alcohol and other impairing drugs are involved in approximately 40% of all traffic crashes in which someone is killed every year.”
   South Dakota Driver License Manual, Handbook p. 19

2. Under 21, it is illegal to buy, possess or drink alcohol.

   Source: Handbook p. 19

   “If under the age of 21, it is illegal to purchase, possess, or drink alcoholic beverages.”
   South Dakota Driver License Manual, Handbook p. 19

3. A BAC of 0.08%, or 0.02% if under 21, is evidence of driving under the influence.

   Source: Handbook p. 20

   “A Blood Alcohol Concentration of 0.08% (0.02% if under 21 years of age) or more is evidence that you were driving under the influence of alcohol.”
   South Dakota Driver License Manual, Handbook p. 20

4. You can be arrested with physical control of a vehicle, even if you are not driving.

   Source: Handbook p. 20

   “If you have physical control of a vehicle (you don’t have to be driving) you can be arrested if your blood alcohol concentration (BAC) is over the legal limit.”
   South Dakota Driver License Manual, Handbook p. 20

5. Vision is affected at 0.02% BAC for all drivers.

   Source: Handbook p. 20

   “Vision is impacted at 0.02% blood alcohol content (BAC) for all drivers.”
   South Dakota Driver License Manual, Handbook p. 20

6. Even under 0.08% you are still impaired and can be convicted.

   Source: Handbook p. 20

   “Even under 0.08%, you are still impaired. Under state law, you can still be convicted for driving impaired.”
   South Dakota Driver License Manual, Handbook p. 20

7. By getting a license you consent to a lawful test of your blood, breath or urine if suspected of impaired driving.

   Source: Handbook p. 20

   “when you get your driver’s license, you have implicitly consented to a lawfully requested test to determine the alcohol content of your blood, breath, urine, or other bodily substance if suspected of impaired driving.”
   South Dakota Driver License Manual, Handbook p. 20

8. Refusing a BAC test can cost you your license for one year.

   Source: Handbook p. 20

   “You can lose your driver’s license for one year if you refuse to take a BAC test.”
   South Dakota Driver License Manual, Handbook p. 20

9. After a DWI conviction you must file an SR22 and keep it for 3 years.

   Source: Handbook p. 20

   “UPON CONVICTION OF DWI, YOU MUST PRESENT AN SR22 “INSURANCE FILING” TO THE DEPARTMENT OF PUBLIC SAFETY AND MAINTAIN THIS INSURANCE FOR 3 YEARS FROM THE ELIGIBILITY DATE.”
   South Dakota Driver License Manual, Handbook p. 20

Numbers to know

3 questions from the South Dakota practice test

1. 1. Under South Dakota's Zero Tolerance law, what BAC range can lead to an arrest for a driver under 21?

   1. Any measurable amount above 0.00%
   2. 0.05% to 0.10%
   3. Only 0.08% or higher, the same as adults
   4. 0.02% to 0.08%
   Show answer

   0.02% to 0.08%. South Dakota applies Zero Tolerance to drivers under 21 at a BAC of 0.02% to 0.08%, a band well below the adult DWI level. Choosing the adult figure misses the point of the law, which is that a young driver can be arrested long before reaching 0.08%. The manual also notes that any measurable amount above zero is not the stated threshold in South Dakota; the number is 0.02%. Once arrested, the driver may be asked to take a chemical test, and consent to that test was given by driving on a public highway.

2. 2. Under South Dakota implied consent, what have you agreed to when you get a driver license?

   1. Automatic guilt for any crash after drinking
   2. A search of your vehicle at every traffic stop
   3. A lawfully requested alcohol or drug content test when suspected of impaired driving
   4. A yearly medical exam by law enforcement
   Show answer

   A lawfully requested alcohol or drug content test when suspected of impaired driving. South Dakota describes implied consent as an agreement connected to licensing and driving: if an officer lawfully requests a test because impaired driving is suspected, you have already consented to testing of blood, breath, urine, or another bodily substance. The vehicle-search choice overstates the rule and changes it into a general search permission. The cue is suspicion of impaired driving plus a requested chemical test; that is when implied consent applies.

3. 3. What license consequence can follow refusal to take a BAC test in South Dakota?

   1. A warning with no license action
   2. Loss of the driver license for one year
   3. A 10-day permit extension
   4. Only a higher insurance premium
   Show answer

   Loss of the driver license for one year. Refusing a requested BAC test carries its own license consequence in South Dakota. The manual says refusal can cost the driver the license for one year. The warning-only answer is wrong because implied consent laws attach a penalty to refusal, separate from any later DWI charge. The cue is the officer’s lawful test request: refusing does not avoid consequences and may create a distinct one-year loss of driving privileges.

Source: the South Dakota Driver License Manual, Be in Shape to Drive. This lesson is a plain English summary, not the law itself; where it differs, the manual and the statute govern. Last checked 2026-09-27.