car legistation

We’ve all read those weird newspaper stories of a driver being arrested for something strange, and had that “I didn’t know that was illegal” moment. Over the years as driving has changed, laws have built up around them, but they might not always seem to make sense.

From odd loopholes to modding mishaps, it’s important that you understand where lines are drawn and what you need to watch out for. So, to help motorists know what’s legal and what’s not behind the wheel, here we look at some of the weirder legal driving issues.

Clocking Your Car is Legal — But Selling a Clocked Car Isn’t

While we aren’t sure why the average driver would want to adjust the odometer mileage of their car, clocking a car (as in, reducing its mileage) is actually legal in the UK. Due to a loophole in the law, it’s not illegal to alter a car’s odometer to make it look like it’s done fewer miles — however it’s probably completely pointless because knowingly selling a car which has been clocked is against the law.

This legal loophole is causing big problems for the motor industry, with recent figures suggesting that cases of car clocking rose by 10% in 2015. New digital odometers are particularly susceptible to clocking, with criminals now able to buy devices cheaply online which can erase thousands of miles from an odometer in a matter of seconds.

To prevent falling victim to a clocked car, the Local Government Association (LGA) and Citizens Advice recommend that all used car buyers check with the DVLA for previous MOT certificates showing the car’s mileage and service history. Visible wear and tear on the car’s steering wheel, pedals and gear stick can also give you a good idea of its actual mileage.

is clocking legal

Speed Trap Detectors — Legal or Not?

Since the dawn of the much-relied-upon sat nav, a flurry of similar gadgets have emerged, including speed trap detectors. This standalone (or in-built) technology gives the driver an indication of an approaching speed camera or trap, so they’ve got time to adjust their speed in line with the limit, and avoidany speeding penalties.

These controversial devices have split opinion, with some motorists fearing that reckless drivers will use them as a way to dodge speed cameras. And it seemed at one stage that the government agreed, as they introduced new driving legislation banning the use of radar and laser-operated speed trap detectors on UK roads. The planned legislation change fell through however, meaning that motorists are still legally allowed to use them if they wish.

However, not every country and region allows you to use speed trap detectors, including the Republic of Ireland — so if you have one and you’re driving abroad make sure you check out the local laws first.

Modified Cars and the Law



Lots of young drivers choose to modify their cars, usually for purely aesthetic reasons. Big bore exhausts, fancy alloy wheels, huge rear spoilers and under-body neon lighting are some of the most popular modifications motorists add to their cars — but are they operating within the law?

Nine times out of ten, if a modification has been added safely and has been purchased from an approved outlet, there shouldn’t be any legal issues. However, there are laws in place banning some types of modifications, particularly if they could result in the driver or other road users becoming distracted.

One of the most common illegal car modifications is an adapted big bore exhaust, which produces noise above the 90-decibel threshold allowed for private vehicles. Police can take action against any driver whose exhaust silencer isn’t keeping engine noise to a minimum, or if they think the person is driving in a way which creates too much noise.

Another illegal modification is after-market window tinting, which is basically a dark film applied to a car’s windows. While tinting rear windows is legal, applying after-market window tints to the front is illegal, and the police will ask drivers to remove it before issuing a penalty notice.

Smoking Whilst Driving — What’s the Law There?

smoke in car legal

Thousands of UK motorists smoke at the wheel, with many choosing to open the driver’s side window to try and oust the fumes. But, given the potential for distraction, is it actually legal to smoke whilst driving?

The short answer is yes, it’s perfectly legal to smoke whilst driving — the same as it’s OK to eat, drink or change a CD. However, if the police have reason to believe you’re driving dangerously or are distracted whilst driving, you could be penalised for not being in proper control of the vehicle.

However, there is one instance in which smoking whilst driving does enter the realm of illegality, and that’s when there are children in the car. To protect youngsters from harmful cigarette fumes, in 2015, the government made it illegal to smoke in any private vehicle with anyone under 18 present. The law is applied under the Health Act 2006, and applies to all cars with a wholly or partly enclosed roof.

Using Your Phone in Standstill Traffic — Illegal or Not?

Given that the ban on using mobile phones whilst driving came into force in 2003, you’d think people would have got the message by now. Sadly, thousands of motorists are still guilty of texting, calling or checking Facebook in the car — giving the government no choice but to double the penalty issued for using a phone at the wheel in 2016.

The problem with the mobile phone ban is that there are a few grey areas, or areas in which drivers think they are immune to the law. One of these is using a phone whilst the car is stationary, with hundreds of people using their phone whilst stuck in traffic.

What motorists often fail to realise is that the law applies from the moment the car is running, and not just when it’s moving. So, if you want to avoid receiving a £100 fine and six penalty points on your license, keep your phone in your pocket, no matter how urgent that call or text might be.

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Image credits: Peter Stevens