Many people face a DUI as the only serious charge in their lives. As they have not been involved in a similar situation normally they don't know what to do. I answer their questions.

Its Friday night.  You stopped to have a couple drinks with co-workers after closing.  As you drive home you are stopped by the police for Improper Traffic Lane Use.  You only swerved because you glanced down at your cell phone.  The officer asks you if you drank any alcoholic beverages tonight.  Your anxiety escalates.  You know he is focused on arresting your for DUI.  But you know you probably aren't under the influence.  The officer asks you to get out of your car.  He then asks whether you will perform field sobriety tests.  What should you do?

Standardized field sobriety testing consists of at least three (3) separate exercises.  Each is created to split your attention between interacting with the police and physically performing the acts properly.  The officer usually gives instructions very quickly.  If you haven't had to perform these tests in the past it is very difficult to listen to the officer and fully understand his instructions.  Each of these "tests" are designed for failure.  Only 65% of all adults can pass these tests without alcohol consumption.  Yes that is correct - 1/3 of all subjects failed the tests even when they hadn't consumed alcohol.  And if the age of the subject is over 65 years the tests have no validity.  Since these tests are geared towards failure a subject is best served refusing to perform them.  That is right.  A DUI subject may refuse the testing.  The best way to do so is to politely thank the officer and advise him/her that you will not perform the test.  Police officers know that they increase the strength of the DUI case if the subject engages in the tests.  Refuse to take the tests.

Next most officers have portable breath testing equipment available to them.  If a subject takes a PBT and the result is over the legal limit they cannot use the result in court.  However, they can testify that based upon the results of the PBT they decided to arrest the subject.  Pretty much the same as telling the court/jury that the subject was over the legal limit.  Never take a PBT.  

Next, the subject is requested to submit a breath sample at the station.  Always refuse this request.  The police will first read a Warning to Motorist that advises a first offender will face a 6 month suspension if they submit a sample over the legal limit.  A first offender who refuses will face a 12 month suspension.  The person can legally drive the entire length of either the 6 or 12 month suspension if they obtain a MDDP (driving permit).  So in reality the refusal will result in a longer suspension and that will cost more money to keep the permit in effect.  But if a subject gives a sample that is .08 or higher game over.  The BAC of .08 or higher creates a legal presumption that the driver was under the influence of alcohol.  A refusal gives rise to no such presumption.  If a subject refuses and performs fairly well on the FSTS a good attorney can usually negotiate a rescission of the suspension or a dismissal of the DUI.  Refusing the BAC is very important.  

Lastly, most officers will attempt to interview the subject after a breath sample has been requested.  Always politely refuse to answer questions.  You may tell the officer "thank you but I want my attorney and I am not answering questions."  You have an absolute right to not answer questions pursuant to your Fifth Amendment right against compulsory self-incrimination.  Use it.  The questions are geared for obtaining statement evidence regarding how much you have had to drink, whether you are under the influence, and if you are oriented.  Always refuse to answer questions.  

In sum: refuse the field sobriety tests, PBT and BAC requests.  And be as polite as possible with the police when refusing to answer any questions.