A guide to drink driving and the law

Deciding whether you're over the limit to drive is not as simple as measuring in how many pints of beer or glasses of wine you've had. The complex ways that alcohol affects your body means that the only truly safe way to drive is to not drink any alcohol at all. 

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Frequently thought questions

Sometimes questions pop into our heads about things we think we should know the answers to – like drink driving. And when you really don’t know the answer you might try and blag it – which is never a good idea. So, let’s take some frequently thought questions about drinking and driving and find out the facts.

What are the legal limits?

In England, Wales and Northern Ireland, the alcohol limit if you’re driving is:

- 80 milligrams of alcohol per 100 millilitres of blood
- 35 micrograms per 100 millilitres of breath
- 107 milligrams per 100 millilitres of urine

In Scotland, the law changed in 2014 and the legal limit is now 50 milligrams of alcohol per 100 millilitres of blood or 22 micrograms per 100 millilitres of breath, which is more in line with some European countries.

What is a unit of alcohol?

We’re all familiar with measuring alcohol in units and know that a certain amount is bad for us; but when it comes to working out exactly what a unit is most of us are as clear about it as the night before the morning after.

Officially, the guidelines are not to drink more than 14 units of alcohol a week for men and women. That roughly works out as six standard (175ml) glasses of wine or six pints of 4% proof lager or ale or five pints of cider.

To put it into context, one unit is 8g or 10ml of pure alcohol and there are just over two units in a standard glass of wine or pint of beer. A large glass of wine contains three units, as does a pint of high strength beer, lager or ale; and if you like downing shots – then each one contains one unit.

So how many units can I drink and still drive?

This is the science bit – and it’s not exact so don’t get your hopes up of being able to sail (or drive) close to the wind. It’s also worth bearing in mind that if you’ve had a heavy night, you might still be over the limit when you wake up the next morning.

To compound the uncertainty of it, alcohol affects us all in different ways and can even affect the same person differently depending on the specific factors at play when they have a drink. Have you experienced that ‘tipsy’ moment after half a glass?

How quickly you process alcohol really depends on multiple factors, such as:

Penalties for drink driving?

In 2015, there were 5,770 drink driving related accidents, with 980 of them being classed as ‘serious’. Needless to say, those 5,770 incidents could have been avoided if those drink drivers had just said ‘no’. So, the penalties are harsh and you could face points on your licence, imprisonment, a fine and a possible ban for driving while above the legal limit - which is increased to three years if it's your second conviction of that offence in 10 years.

If you are disqualified from driving, a judge might offer you a reduction in the amount of time you’re off the road for if you go on a drink driving course.

It’s also worth noting that if you’re asked for a blood sample and fail to do so, then it can be treated just as severely as a failed test and you could face an unlimited fine, a 12 month driving ban, and even 6 months in prison.

If you cause death whilst driving under the influence of drink, depending on the circumstances you could face 14 years in prison, an unlimited fine, points on your licence and a two year ban – plus an extended driving test before you can your licence back.

How does a drink driving conviction affect my insurance?

Driving convictions are likely to increase the cost of your premium and you might even find it hard to get cover at all.

If you’ve been with the same insurance provider for a while and have historically had a good driving record, then it might be best to stick with them rather than trying to find another. But if you can’t renew your insurance then there are specialist companies that can help you. However, the hard truth is, that whoever insures you, getting cover with a conviction is likely to be expensive. If you do go on a drink drive rehabilitation course, then this will be in your favour as some insurance providers see this as a positive thing.

You can help lower the cost of your insurance by doing things like increasing your excess (although make sure you can still afford it). The total excess is a combination of a voluntary and a compulsory. You will probably have a higher compulsory excess with a driving conviction. You could also add an experienced named driver with a spotless driving record to your policy which could possibly lower the cost.

Another way of reducing your premium post-conviction, is to limit your mileage – the fewer miles you do, the lower your premium is likely to be. But be truthful, saying you’ll only do 5,000 miles when you drive for four hours every day will only wind up with your policy being invalidated if caught out or you being charged an additional premium to rate the policy correctly.

Increasing the security of your car could also help with insurance costs – if you can’t park it overnight in a secure garage or driveway then adding an approved security system or immobiliser could help.

Always remember…

Driving when you’re drunk is a bad thing and no drink is worth the risk. If you’re on a night out, organise a taxi or agree who’s driving – simple planning means you can all still have fun and not worry about who’s still sober enough to get you all home. But if you do end up with a conviction then it pays to compare quotes to make sure you get the best deal possible for your circumstances.