Driving myths

Debunking myths about driving

Some myths get passed around so much they become confused with fact. We’ve all heard the likes of “swallowed chewing gum stays in your system for 7 years” and “we only use 10% of our brains.”

Driving has its fair share of myths too, so we've looked at the most common ones, 16 of them in fact – to separate the good advice from the nonsense.

Man eating while driving - is it illegal?

1. Is it true I can drive 10% over the speed limit without breaking the law?

In theory, driving even 1mph over the speed limit could land you in hot water. But you won’t get a ticket because speedometers aren’t always 100% accurate, so police allow for this. Plus, it’s not safe to drive with your eyes glued to the speedo. AA President Edmund King advises that it’s better to keep your eyes on the road.

The National Police Chief’s Council recommends only giving a speeding ticket if you top the limit by 10% plus 2. So that would mean driving 35mph in a 30mph zone. However, this is up to individual police officers to decide, so there’s no guarantee they’ll let you off.

The best way to make sure you don’t get caught by a police officer or speed camera is to drive carefully and try to stick to the limit.

2. Can you drink alcohol as a passenger in a car?

It’s not illegal to drink alcohol as a passenger, but just because you can, it doesn’t necessarily mean you should. After all, it’s not just the driver's responsibility - passengers can help with safer driving too.

If you're supervising a learner driver, the same legal responsibilities apply to you. So you can't use your phone or be under the influence even though you're not doing the actual driving yourself.

Can you drink while driving?

No, you can’t drink alcohol while driving, as even 1 drink could put you over the legal drink-driving limit. On top of that, being focused on drinking means you won’t be as focused on the road ahead of you.

Police will pull you over if they see you drinking alcohol as the driver of a vehicle, with a breath test following. Our best advice? Just don’t do it!

3. Can you drink alcohol-free beer while driving in the UK?

There is nothing technically illegal about drinking alcohol-free beer while driving in the UK, however, you can still expect to get pulled over for it if your drink looks similar enough to a real beer bottle or can (which most alcohol-free beers tend to do). Again, our best advice would be to save time and hassle and wait until you’ve completed your journey before drinking anything.

4. Can you have open alcohol in your car?

There’s no law against having an open can or bottle in the car, but it's not recommended to drive around with a backseat full of open beers.

If you’re pulled over and you’ve got a car full of open bottles of booze, you could be breathalysed to make sure you haven’t been drinking.

5. Will sucking a penny fool a breathalyser?

There’s an urban legend that sucking on pennies can mask the alcohol on your breath and cheat a breathalyser. It's illegal and irresponsible to try to cheat a breathalyser as it puts you and other road users in danger. The myth is also nonsense.

Chewing on garlic, citrus or mints won't trick the breathalyser, either. Just don't drink and drive.

6. Is it illegal to eat and drive?

No, there's no specific law against eating while driving. You're not going to be immediately pulled over if you’re seen taking a bite out of your breakfast on the way to work - unless that bite stops you paying attention to the task at hand.

Our Populus poll in December 2018 found that 1 in 10 of us eat while we drive. If you do, make sure your eating habits don't distract you behind the wheel. If the police think you aren't in proper control, you can be charged with careless driving. This carries a maximum penalty of £5,000, 3 to 9 points on your licence and a discretionary driving disqualification.

You’ll also need to consider stopping distances. Because eating makes your reactions slower, you should wait until you’re parked up or stationary to take a bite. This is especially true if you’re driving in bad weather, as stopping distances increase on wet road surfaces.

7. Can you smoke while driving?

It’s illegal to smoke in any private vehicle with anyone under 18 present and in company vehicles or vans. If you use your own private vehicle for business occasionally, you're allowed to smoke in it. If the car has been given to you by your work for the purpose of work, you can't.

It’s not against the law to smoke in the car in any other circumstances, but the Highway Code specifically lists smoking as a distraction that can land you with a careless driving charge.

Read our advice about smoking and driving.

8. Driving barefoot – is it really against the law?

Driving without shoes isn’t illegal, contrary to what many people believe. When choosing which shoes you drive in, you need to be able to operate the pedals safely without your footwear - or lack of - making it difficult. Essentially, you may want to think twice before driving barefoot, or in 6-inch stilettos for that matter.

9. Is driving in flip-flops illegal?

Rule 97 of the Highway Code makes it clear that drivers must have "footwear and clothing which does not prevent (them) using the controls in the correct manner." So while it's not illegal to drive in flip-flops, it's suggested you drive in more sensible shoes. Flip flops can come off easier, or end up slipping under the pedals and getting stuck.

10. Is it legal to drive with the interior light on?

It’s very possible that at some point as a child, your parents told you that turning the car's inside lights on while driving was a crime. It’s something which lots of people think is a fact but there’s no law against driving with your interior lights on. But at night it can be distracting or interfere with your vision by reflecting off of the inside of the windscreen.

If you’re pulled over and it’s decided that your light was a probable cause in any bad driving, you can expect to get a careless driving charge though.

11. Is it illegal to drive around a roundabout 3 times?

No, it isn’t. Roundabouts aren't always the easiest to navigate so don't worry about missing your exit the first time. But you should plan your route in advance so you don't end up circling unnecessarily, as this could be considered careless driving.

12. Can fuzzy dice fail my MOT?

Yes, they actually can. Obstruction of more than 4cm could land you with a failed MOT. But realistically you’ll probably be told by your mechanic to remove the dice before the MOT takes place.


Winter driving myths

Driving myths aren’t just limited to the summer months – winter brings up its fair share of driving misconceptions too. Don’t worry, we’re here to put those misconceptions to bed:

13. Is it better to have lower tyre pressure in the winter?

Some say that reducing tyre pressure in the winter months means you’ll get better traction when driving in snowy or icy conditions. However, this isn’t true. In fact, it may make matters worse!

You’ll actually find yourself with an increased stopping time, potentially skidding more on wet surfaces, and with reduced fuel economy. We’d suggest making sure your tyres are at the recommended pressure in the winter.

14. Is it illegal to drive with snow on your car in the UK?

It’s not outright illegal to drive with snow on your car in the UK, however, the Highway Code states that you must be able to see out of every window on your vehicle. If your visibility out of any window is reduced then this could be deemed as dangerous driving, which of course IS illegal. Make sure to take a look at our winter driving advice before heading out in the snow.

15. Do tyres deflate in cold weather?

Yes, cold weather leads to tyre deflation. In some cases where it’s only cold overnight and the temperature remains stable in the day (providing you have no holes in your tyres), you can expect your tyres to return to their normal pressure by themselves. In the winter months, you should check your tyre pressures every 2 weeks.

16. Can you defog a car windscreen with a potato?

While it’s a fun idea, in truth all this does is waste a potato and cause you to have a dirty windscreen. You’ll then need to clean your windscreen for proper visibility or risk breaking the law.

What does the Highway Code say?

The most important thing to remember when you're on the road is that you must obey the Highway Code. Rule 148 of the Highway Code states that safe driving and riding needs concentration, so all distractions should be avoided.

Distractions include:

  • Too much focus on talking to your passengers.
  • Reading maps.
  • Fiddling with the aux cable, radio, CDs or other controls.
  • Listening to loud music.
  • Eating and drinking.
  • Smoking.

There might not be specific laws forbidding certain actions and behaviours, but it's strongly recommended that you avoid doing anything that could slow your reaction times and cause an otherwise avoidable accident.

How many drinks can I have and still drive?

When it comes to the drink-driving limit, our stance is: if you’re driving, don’t drink at all.

How much you can drink and still be safe to drive varies for each person, so there is no fixed answer. Factors including your weight, metabolism, gender, and what you’ve had to eat contribute to how you process alcohol. That means it’s impossible to say that, for example, 2 glasses of wine is how much you’re allowed.

Know your limit

As far as the law goes in England and Wales, the alcohol limit for drivers is 80mg of alcohol per 100ml of blood. In Scotland, it's 50mg of alcohol per 100ml of blood. Different people will reach this limit after a different number or type of drinks - a strong cocktail will have more effect than one cider, for example.

Attempting to drive while above the legal limit can get you 6 months in prison, an unlimited fine and a driving ban. So it’s better to just not risk it and avoid a drink if you’re the designated driver.

Read more on drink-driving laws in the UK.

Should I drink soft drinks and coffee while driving?

Just like with eating, there’s no law against drinking a soft drink while driving, if you aren’t distracted by it. So, if you’re driving with a hot coffee cup, keep the lid on. Any sudden spills could be enough to cause you to lose control of the car and you could end up with a careless driving fine - as well as a burnt lap.

If your coffee spill causes you to get in a serious accident, you could be prosecuted for causing death by careless driving. You could be banned from driving, handed an unlimited fine, or given a prison sentence of up to 5 years.

Drinking other soft drinks is also fine as long as you keep your attention firmly on the road. It’s actually recommended that you drink water before driving and keep hydrated throughout a long drive. Not drinking enough water can have the same effect on you as drink driving.

Published: 25 June 2019 | Updated: 30 November 2023 | Author: The AA

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