While you are not required to perform a Preliminary Breath Test/PBT conducted roadside, your refusal to do so will potentially allow for the officer to determine there is probable cause for further detention and testing. On the other hand, it is against the law in Minnesota for you to refuse the breath, urine or blood test down at the police station after the Minnesota Implied Consent Advisory is read by the officer. Failure to submit to chemical testing at the police station will put you at risk of losing your license for a year and being charged with the crime of Refusal in Minnesota .
Do not perform field sobriety tests.
Are you being asked to perform a series of tests, such as walking in a straight line, standing on one leg, or following a moving object with your eyes? The officer is doing so because he wants to test your coordination. It is important to remember that all field sobriety tests are optional, but police officers will never voluntarily disclose this information. More importantly, such tests may be offered as evidence against you at trial by the prosecutor.
Decline warrantless searches.
You are under no obligation to consent to an officer’s request to search your vehicle and belongings. The officer may be asking to conduct a search because he or she doesn’t have substantial evidence to convict you of your DUI charge.
Be courteous.
If you are pulled over, simply shut the car engine off, roll down your window, and keep your hands planted on the steering wheel. Retrieve your documents only when the officer asks to see them. Refer to the officer as “officer”, “sir” or “ma’am”. You may be under a stressful situation, but be polite and non-confrontational throughout the entire traffic stop in order to prevent making the situation any harder than it needs to be.
Source: www.motorists.org