Special reasons: faulty home breathalyser

The Alcosense Elite is the breathalyser I use at home

Many of us keep a breathalyser at home to check that we are safe to drive the day after drinking (okay and maybe sometimes to see who can handle their drink best) but what if the machine gets it wrong?

At heart, most of the home breathalysers work using an infrared detector to count the number of alcohol molecules passing over the sensor; this is exactly how the police’s roadside breathalysers work.  It’s even how the Camic Datamaster and Lion Intoxilyser (two of the three evidential breath machines used in police stations) work – the Intoximeter EC/IR uses both infrared and fuel cell technology.  Given that they use the same technology as their professional counterparts you may well assume that the home breathalysers will be as reliable, but some reports have suggested that the home breathalysers are unreliable.

We are solicitors not toxicology experts so we are not going to consider the reliability of home breathalysers.  Instead we will look at what happens if you rely on one only to be let down.

Let’s clear one question up right away – if your breathalyser says you are under the limit but the police say you were over the limit, can that be a defence? No.  The law is quite simple, if you drive on a road or other public place with excess alcohol you are guilty of drink driving, it doesn’t matter why you did it.

But, the really interesting question (well to me, but then I am a solicitor who specialises in drink driving law) is whether reliance on a home breathalyser can amount to a special reason for not disqualifying.

Now, the court must disqualify a drink driver for a minimum of 12 months unless there is a special reason not to do so.  Way back in 1939 the High Court in Northern Ireland said that a special reason is something that should be considered by the court when it passes sentence and should be “directly connected with the commission of the offence”.  This was incorporated into English law when Lord Goddard gave judgment in the 1946 case of Whittal v Kirby.  But, it wasn’t until 1958 in the case of R  v Wickens that we finally got the modern definition of a special reason.  Mr Justice Devlin set out four points for a defendant to prove if he wishes to avail himself of special reasons.  The reason must:

1.       Be an extenuating or mitigating circumstance;

2.       Not amount to a defence to the allegation;

3.       Be directly connected with the commission of the offence;

4.       Be one that the court should properly take into account when imposing sentence.

This test has been severely restricted by subsequent cases; however, I have yet to find a case where somebody has relied on a malfunctioning breathalyser as a special reason – though this area of law is hardly fast moving when the main cases are over half a century old.

Broadly speaking special reasons in drink driving can be split into three categories: those explaining how the defendant came to be over the drink driving limit; reasons explaining why he or she drove above the limit; and anything else.

Let’s think about our situation where a man, we’ll call him Gary, has been out drinking one evening.  The following morning, he gets up, feels fine and blows into his breathalyser.  The breathalyser shows a reading of 20 mg of alcohol per 100 ml of breath, a reading well below the drink driving limit.  Gary decides he’s safe to drive.  Shortly after leaving home, Gary is involved in a minor road traffic accident, the police arrive and breathalyse him.  The roadside test comes back showing Gary is over the limit – the evidential breath test at the police station confirms this and Gary is charged with drink driving.

Gary’s account is one that explains why he drove while over the limit.  But does it meet the other criteria?

Is being misled by a malfunctioning breathalyser mitigating or extenuating?  I would say that it is because it goes to show that Gary was being careful and attempting to avoid drink driving – it was not something that he set out or wanted to do.  That is mitigating in my book.

Is Gary’s account a defence in law to drink driving?  Nope.

Is his account directly connected with the commission of the offence?  Yes.  If Gary is to be believed, he was being as careful and would not have driven had the breathalyser indicated he was over the drink driving limit.  He therefore only drove because he was misled by the device he purchased to prevent him drink driving.

Should the court take this into account when passing sentence?  That’s a matter for the magistrates but I would be surprised if a court said no.

So, on the face of it a misleading reading from a home breathalyser is capable of amounting to a special reason.

If you have been accused of drink driving you can get expert legal advice from London Drink Driving Solicitor on 020 8242 4440.