Can Police Breathalyse You on Private Property?

Under the Road Traffic Act 1988, police in England and Wales have powers to require a specimen of breath if they suspect you are driving, have driven or are ‘in charge’ of a motor vehicle on a road (or public place) while over the alcohol limit. This usually means that the police will administer a breathalyser test if you are involved in a road traffic accident or if your driving conduct leads them to suspect that you are driving while above the legal alcohol limit.

However, because the law specifies that you must be on a road (or public place), there is sometimes ambiguity about whether you can be breathalysed on private property, and under what circumstances. In fact, there are complex rules about when the police can ask you to take a breathalyser test on private land. Even if land is privately owned, it may be treated as a “public place” for the purposes of drink driving offences if there is public access or right of way, which means you may be subjected to a breathalyser test or asked to provide a sample in some situations.
At the same time, the police must follow careful procedures when collecting forensic evidence for use in prosecuting these offences, and any mistakes or procedural failings can be used as part of your defence. Here, the expert drink driving solicitors at JMW outline the circumstances under which you may be asked to give a breath sample on private land, the consequences you may face for refusing to give a breath, blood or urine sample following a road traffic accident, and the defences you may be able to rely on if you believe that there were procedural errors made during the collection of evidence.

When Can the Police Ask for a Breath Sample on Private Land?

The police can stop you and ask you to take a breath test if you have been driving or are attempting to drive and they reasonably suspect you have been drinking. If you have committed a traffic offence, or been involved in a road-traffic accident, this can also trigger a request for a breath test, followed by a breath, blood or urine sample to confirm the results of the initial test.

The police do not have a general right to enter your home or private property simply to require a preliminary breath test, unless you have left the scene of an accident or if they have power of entry under other legislation. Because the threshold for requiring the test is that the officer reasonably suspects you are driving and you might be over the limit, they cannot simply randomly require a test on private land without such suspicion.

However, if there is public access or right of way they may be able to enter the property and ask for a breath sample. Similarly, if you are ‘in charge’ of a vehicle on private land to which there is public access, the police may ask you to follow the breath test procedure. If you have been driving (or attempting to drive) a vehicle and you’re in a location that is treated as a public place in law, even if it is privately owned, then the police may lawfully require a breath test - for example, a car park that is owned by a business but which is open to the public may be considered a public place under the law. However, the burden is on the prosecution to prove that private property represents a public place, which can help your defence.

If there has been an accident involving injury and the police believe you were involved and may have been above the legal limit for alcohol, they may have the power to enter private premises (with reasonable force) to require a breath test.

Can You Refuse to Give a Breath, Blood or Urine Sample?

If the police ask for a sample and you refuse to give one, you will likely be arrested and charged for the offence of failing to provide a specimen. This is a separate offence from drink driving, and the police do not need to prove that you were over the limit for this offence to apply. The offence is your refusal or failure to provide the sample when required, and it comes with many of the same penalties as a drink driving offence. A conviction for failing to provide a specimen triggers a mandatory driving disqualification of at least 12 months, and can lead to penalties including:

• Up to six months’ imprisonment.
• An unlimited fine.
• A criminal record (which may impact employment, insurance premiums and travel opportunities).

If you have a previous drink or drug‐driving conviction within the last 10 years, the minimum disqualification can increase, and the court will treat this as an aggravating factor. This means you can receive a harsher penalty, even if it has not been proved that you were above the legal limit when you refused to provide a specimen.

As such, it is usually unwise to refuse to give a sample unless you have what the law calls a "reasonable excuse". Having a reasonable excuse generally means that you had a medical condition such as severe asthma or lung disease that prevented you from giving the sample. There are other valid reasons that can apply in these cases, but the burden is on you to prove the excuse. As such, it is important to work with a driving offences solicitor to mount your defence if you refused to give a sample and are facing a charge as a result.

Similarly, if you believe you are being asked for a sample under illegal circumstances, you should comply with investigators and speak to a solicitor at your earliest opportunity. The police are bound by strict rules when gathering evidence and if prosecution evidence was collected incorrectly or illegally, this can work in your defence. The motoring offences solicitors at JMW can advise you on challenging illegally obtained breathalyser results and help you to mount a legal defence against any underlying charges on this basis.

What Are the Defences for Drink Driving Charges on Private Land?

There are a number of defences that may be used to defend an alleged drink-driving offence on private land. It is important to consult an experienced motoring offences solicitor at your earliest opportunity so that you can begin to mount a defence from the outset of your case, as this can make a big difference to your chances of success.

If you can show that you were on private land that does not constitute a public place, this may act as a defence. The law stipulates that the offence of driving (or attempting to drive) over the prescribed alcohol limit applies when a person drives “on a road or other public place”, and if you can show the vehicle was only driven on land that does not amount to a “road or other public place”, the prosecution’s case may fail at that first hurdle.

Just because land is privately owned, this does not automatically mean it is “private” for these purposes. The prosecution must prove that the land is public, and your solicitor can challenge the evidence to show that the land was, in fact, private property. If the land is genuinely private (for example, a gated estate with no public access and no implied right of way), then the offence may not have been committed. The test is fact-specific.

Another defence that may apply, especially on private land, is called post-drive consumption or the “hip-flask defence” in colloquial terms. When a defendant can show that they had finished driving long before their breathalyser sample was collected, and they drank alcohol after they had stopped driving but before the breath/blood test was taken, this can act as a defence. While it can be challenging to demonstrate you were below the legal limit at the time of driving, an expert “back-calculation” may be used to estimate what your alcohol level would have been at the time you finished driving. The team at JMW can support you to gather evidence and build a case in your defence.

As we have noted, mistakes or non-compliance in police procedure regarding testing, arresting or charging, can give rise to defences. For example, if you can prove that the breath-testing machine was not properly calibrated or maintained, or that the chain of evidence has not been correctly established, this can work in your defence. Even if you were above the limit and the place was deemed a public road, procedural flaws may lead to the evidence being inadmissible or the prosecution offering no evidence. Your solicitor will scrutinise every stage of the stop, testing, and documentation.