It is VERY dangerous to drive with one hand, you severely impair your reaction time in case of an emergency. As a driver for many decades, I can tell you that bad luck will always come when you LEAST aspect it.
Most people that were involved in avoidable accidents say the same thing- they thought it's okay to not wear seatbelts because they feel in control, no need to wear helmet because it's a short ride, etc but guess what, these are the people who get injured in accidents, or worse.
It always saddeneds me that people don't respect the road and will only follow the law when it's forced upon us. I don't care about the law, I want to keep me and my family safe when I'm driving and that means doing everything I can to mitigate any risks of avoidable accidents, including using one hand to drive.
My advice? Don't worry about polis saman, worry about not loosing a a limb, a family member or being 6 feet under because you feel like the car is under your full control despite driving incorrectly. My friend said something once, the roads are like the battlefield, only filled with negligent civilians rather than skilled soldiers.