Probable cause to arrest

If the officer has sufficient probable cause that the suspect has been driving under the influence of alcohol, they will make the arrest, handcuff the suspect and transport them to the police station. En route, the officer may advise them of their Miranda rights and their legal implied consent obligation to submit to an evidentiary chemical test of blood, breath or possibly urine.
Laws relating to what exactly constitutes probable cause vary from state to state. In California it is a refutable presumption that a person with a BAC of .08 or higher is driving under the influence. However, section 23610(a)(2) of the California Vehicle Code states that driving with a BAC between .05 and .08 "shall not give rise to any presumption that the person was or was not under the influence of an alcoholic beverage."