Miranda rights are not required to be read at the scene when the police are performing the initial field sobriety tests. This is because the courts have determined that at that point the officer is still in the investigative phase where he is trying to determine if you are intoxicated.
Because he is not “interrogating” as defined by the courts, field sobriety tests at the time of the stop do not fall under Miranda.
If the field sobriety tests are performed after you are under arrest and are transported to the police station, Miranda rights are required to be read. If they are not, any tests or statements you make after the point they should have been read may be excluded from evidence.
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