It's just the wrong thing to do. The law here says that if you have a Bluetooth you may not get pulled over but if you have your phone in your hand you will. Whether you THINK your attention is all on the road or not is beside the point; it's not. Even subconsciously, you're concentrating at least partly on the phone and the call and what's being said and what you're saying and what you want to say and how the guy is wrong and you're gonna tell him and how you're going to OH **** WHERE DID THAT TRUCK COME FROM!!!????
See?
No matter what, if your attention isn't 100% on the road you're driving dangerously and you deserve to be stopped. I don't drive but I've seen my brother do this, and it's ****ing scary. He'll talk as if he's at home and you're like WATCH OUT FOR THAT KID CROSSING THE - never mind.
buy yourself a bluetooth and handsfree set.
And don't complain like a bitch when they stop you otherwise.
Oh, and great idea to further antagonise a cop who has just given you a ticket by throwing attitude at him. Is that tail-light broken sir? Oh well it is now.