Can a cop refuse to tell you why you are arrested and delay your Miranda rights?
An officer is not legally required to tell you why you are being arrested or what charges you might face. If you ask, “Am I free to go?”, they are required to inform you if the answer is no. It is actually the local prosecuting attorney who has the final call on charges not the officer, and that attorney will not review your case until some time after you are arrested. So, whatever the officer tells you (for example, “You are under arrest for Assault 4 DV.”) is ultimately meaningless.