What is illegal to do while driving under all circumstances?

Using a handheld mobile phone while driving is illegal under all circumstances primarily due to the high risk associated with distracted driving. When a driver engages with a handheld device, their attention is diverted away from the road, significantly increasing the likelihood of an accident. Research consistently shows that using a mobile phone while driving can impair reaction times and reduce situational awareness, similar to the effects of alcohol consumption.

Legislation has been put in place in many jurisdictions to combat this. The primary goal is to ensure the safety of all road users by minimizing distractions that can lead to dangerous driving behaviors. Other tasks like eating food, adjusting the radio, or talking to passengers may also distract drivers, but they are not universally illegal and can be done safely if managed properly. Therefore, the use of handheld mobile phones is uniquely prohibited at all times while driving to promote road safety.