Wiltshire drivers have been warned checking the time on their phone while behind the wheel could land them with a driving ban and a £1,000 fine in the most serious cases.
Laws concerning the use of handheld devices have been tightened in recent years following research highlighting their potential to distract drivers.
Taking calls, sending messages, and posting on social media are all prohibited by law, and phones can only be used as sat-navs if they are fixed in position, and the journey is planned before setting off.
However, one lesser-known rule is that "illuminating the screen" is considered an offence.
Mark Tongue, joint CEO of vehicle leasing firm Select Van Leasing, said: "You would have to have been living under a rock not to know how seriously the authorities take the offence of driving while using a mobile phone or smart device.
"There have been numerous campaigns to spread awareness, and it does seem that the message is getting through to most people.
"But there are always some who insist they are above the law and continue to use their phones in extremely dangerous circumstances.
"However, there are also plenty of people who don’t realise that even a quick press on the screen to check the time can land them in trouble."
Section 110 of the Road Vehicles (Construction and Use) Regulations 1986 states: "No person shall drive a motor vehicle on a road if he is using a hand-held mobile telephone."
It goes on to outline what defines usage, which includes “illuminating the screen” and “checking the time”.
According to Department for Transport figures, there were 15,300 prosecutions for "using or causing others to use a handheld mobile phone whilst driving" last year.
Most people caught will face a £200 fine and six points on their licence, but this can extend to a driving ban and £1,000 fine in more serious cases.
Mr Tongue said: "The message here is to consider your smartphone completely off limits while you are driving.
"If you do want to use it as a sat-nav, buy a decent holder - which are fairly cheap online - and programme in any routes before you set off, including scheduled stops.
"While it is not against the law to answer a call using a Bluetooth speaker system that most modern cars have, it’s worth remembering that this can also be a distraction."
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