So, you get arrested for DUI/DWI in Maryland, what do you do? The trial Judge may ask the arresting police officer if you were "polite and cooperative" and the officer's response can, in some instances, play a role in what the Judge does with you. However, what does this really mean?
If you were charged with a more serious crime than DUI you would know that you have rights, Miranda rights that is and hopefully you would know to stay quiet and say nothing until you had the benefit of sage wisdom of counsel. However, in DUI arrests, the Miranda warnings are rarely imparted upon suspects. Is that legal you ask? Well, in a word, yes. It's legal. Reason: Miranda warnings are not a requirement for a legal arrest. They are a requirement for the police to gain admissible information following a legal arrest.
Thus, in the DUI DWI scenario, the I/O or investigating officer is perfectly within her rights to arrest you and never give you the Miranda warnings. However, there are two things you want to know. One: after you are actually arrested (handcuffed) anything she asks you then requires the Miranda warnings or your response is not admissible. Two: the police typically ask you all the damning questions prior to the actual arrest (ie. the handcuffs). They can do that. If they gather oral evidence against you prior to the arrest, no Miranda warnings are necessary at all as the courts have determined that you are not arrested and therefore don't need said advice.