DUI Probable Cause
Probable cause is a key element in any DUI investigation. Police officers are required to follow proper protocol when stopping a vehicle--and that includes having probable cause for the stop. For instance, police cannot just pull your vehicle over because they want to. They must have observed you violating a traffic law (speeding, swerving, etc.). Assuming that you were violating a traffic law, the police officer cannot just suddenly start launching into a DUI investigation. Remember, they pulled you over for a traffic violation only.
If the police officer notices open alcohol containers in your vehicle, smells alcohol coming from the vehicle or observes strange behavior on the part of the driver, then the officer has probable cause to start a DUI investigation. But if the officer doesn’t observe anything like this, you should be free to leave.
If the officer did have probable cause to begin a DUI investigation, you will be asked to take a field sobriety test and a breath test. Listen to the officer’s instructions and perform the tests to the best of your ability. Once the officer completes his observations of you, he or she cannot arrest you for DUI without considerable evidence that you are intoxicated. For instance, you must have ‘failed’ the field sobriety and breath test.
As mentioned earlier, probable cause is a very important part of a DUI investigation. Your defense attorney will question the prosecution to ensure that police had probable cause to stop, detain and arrest you for DUI.
If the prosecution cannot prove that probable cause existed beyond the stop, then any evidence that the state collected against you can be suppressed in court. The only exception to this is the officer’s observation of your driving.
This means that your breath test and/or field sobriety test results may not be allowed to be introduced as evidence against you. This would make the prosecution’s case against you much weaker—remember the burden of proof lies with them.
If you feel that probable cause was lacking in your DUI investigation, speak with a local attorney right away as this could be a defense to your case!



