When you step behind the wheel to drive, then drive.
Whether you have a blue tooth earthingy or not it is a distraction. Doing anything that distracts you from the primary task of driving increases your risk of an accident, including talking to passengers, tuning the radio, it does not matter. I find myself distracted even without cell phones.
I have been rear-ended five times by phone talkers and have been hospitalized as a result of the incidents. They were not accidents because there was a cause. There is no such thing as an accident. All accidents are preventable.
Talking on a cell phone while driving where I work is a termination offense and it is enforced. I have always pulled over to answer or make a call and stop in a safe place. I miss lots of calls but I need to keep my job. If someone calls me and I answer (not driving) and they are driving I tell them to call me when not driving and I hang up. This includes my family. They are getting better. My wife is doing the same thing a lot now.
Anygunanywhere