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Minnesota DWI Laws: Should You Take or Refuse the Test? (Part 3 of 3)

Posted by attorney Jay Carey

Can a Driver Request and Obtain an Additional, Independent Test in a DWI Case?

Yes, a driver has the right the right to request and obtain an additional, independent blood or urine test from a third party at the driver's own expense. The police cannot prevent or deny a driver from contacting a third party like from visiting a person in custody and administering an independent blood or urine test. Such a test typically will cost a driver about $400. If a driver wants an independent test, he must insist that the police allow him to contact a provider to visit him in custody. If the police prevent the additional test, the breath, blood, or urine test administered by the police may be excluded as evidence at trial due to the violation of one's right to an independent test.

An independent test should be administered as soon as practicable because alcohol dissipates in one's body. If a driver waits too long to obtain an independent test after submitting to the State's test, the usefulness of the independent test may be diminished significantly.

Can a Blood or Urine Sample Obtained by the Police be Independently Tested before Trial?

Yes, a person charged with DWI has a right to retest the blood or urine sample before trial. A retest will cost the person approximately $300. Doing so can be quite useful, especially if the alleged alcohol concentration is close to the relevant legal limits of 0.08, 0.16, and 0.20.

Will a Blood or Urine Sample be Tested for Both Alcohol and Controlled Substances?

Generally, no, unless the driver's alcohol concentration is below 0.08 or an accident causing bodily injury occurred.

The State's crime labs will only test a blood or urine sample for alcohol if the driver is suspected of being under the influence of alcohol, even if the driver also admits to use of a controlled substance. If the resulting alcohol concentration is 0.08 or more, the State generally will not test the sample for controlled substances because such testing is costly, time-consuming, and redundant in the typical misdemeanor or gross misdemeanor DWI case. If the case involves felony Criminal Vehicular Operation, the State likely will test a blood or urine test for alcohol and controlled substances. If the resulting alcohol concentration is less than 0.08 in a typical DWI case, a prosecutor may request the State's lab to perform testing for controlled substances.

Should You Take the Preliminary Breath Test Offered at the Roadside?

Yes, most drivers should take the preliminary breath test (PBT) that the police offer a driver at the roadside prior to arrest. A driver who refuses the PBT will be arrested even if his alcohol concentration is under the legal limit. The PBT can be useful to determine if a driver is likely 0.16 or more, and whether a first-time offender should submit to the official test at the police station or jail facility.

The result of the PBT cannot be used to revoke a driver's license or to impound license plates. It is simply a screening test that lacks sufficient reliability to be admissible at trial to prove a driver's alcohol concentration. However, if the driver ultimately refuses to take the official breath, blood, or urine test at the police station or jail facility, the PBT is admissible at trial to prove the elements of Test Refusal.

If a driver is involved a serious accident causing injuries to another person, the driver should not take the PBT and should speak with a lawyer before he decides whether to submit to the official breath, blood, or urine test at the police station or jail facility. The legislature has created a substantial incentive for a driver in an accident causing injury to refuse all testing due to the elements of Criminal Vehicular Operation.

Drivers who refuse both the PBT and the official often receive a "probable cause hold" when booked in jail, even in a first-time offense. These drivers will either be forced to post maximum bail or bond ($12,000) or will wait one to four days to be released by a judge or by the expiration of time limits.

After Arrest, Should You Talk with Police about the Facts of Your Case?

Absolutely not. Drivers who are arrested for DWI should remain calm, polite, cooperative, and quiet. Drivers must cooperate with the testing decision, i.e., take or refuse the test, but drivers should not discuss the facts of their case with the police or with anyone other than a lawyer after a DWI arrest. Anything a driver says can be used against him in court.

Police generally do not give a driver a Miranda warning until after the driver takes or refuses the official test. After the testing decision, a police officer often will read a Miranda warning to a driver and ask the driver if he will agree to answer a few questions without a lawyer present. A driver should politely decline to answer any questions preceded by a Miranda warning. The police will not treat a driver any better if he agrees to such questioning. It is a common misconception that being "cooperative" with these questions will help a driver avoid jail time.


A driver arrested for DWI should speak with a DWI defense lawyer prior to deciding whether to submit to testing. The testing decision is more complex than it may appear. A lawyer will provide a free consultation that can significantly impact one's case. There is virtually no downside to obtaining a free consultation before the testing decision. Regrettably, approximately 80% of people arrested for DWI do not attempt to consult with a lawyer before deciding to take or refuse the chemical test offered by the police.

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