Keep Testing

[ManxTaxPayer]

Until you get the result you need. And if you don't get the result, get an expert to estimate it instead. Bit of a strange one. 

[wrighty]

Probably another one where the reporting is inaccurate and/or we don’t know all the facts. Two pints? Yeah right. Blood and breath alcohol will be undetectable morning after two pints the night before. And if he tested negative, why would they have gone to the bother of getting an expert estimation?

[Roger Mexico]

3 minutes ago, wrighty said:

Probably another one where the reporting is inaccurate and/or we don’t know all the facts. Two pints? Yeah right. Blood and breath alcohol will be undetectable morning after two pints the night before. And if he tested negative, why would they have gone to the bother of getting an expert estimation?

It's still a bit odd though that he was tested shortly after the crash and found under the limit and yet the expert claimed that he would have been 40% over at the time of the crash.  Probably bad reporting but I wouldn't have thought levels would drop so fast so long after ingestion.

[John Wright]

Back calculation is normally used where someone has consumed alcohol after stopping driving, but before the police attend the scene.

But not always. The crash is, I think, a red herring. He wasn’t charged with the crash, but with drink driving.

It all becomes clear, when you look at a time line.

First, the road side test is not directly quantitative. It shows alcohol, over a certain level, but not if it’s 1, 1.2, 1.4, etc over the drink drive limit. Only the reading on the intoximeter at HQ is calibrated and quantitative.

So, driver sets off from home in Beach Street, crashes at Archallsgan, police are called, they arrive, blows clear roadside test, is transported to HQ in Douglas, processed into custody, then undergoes a lion intoximeter test.

Id say that takes 90 minutes. 

The limit in breath is 35ug per 100ml breath.

Lets say he blows 30.

The body eliminates approximately 10ug to 20ug per hour. Average is 15ug.

So, when he left home he’d have been 15-30ug higher at 50-65ug. Both are above the 35ug limit. Giving benefit of doubt, and calculating at minimum elimination rate, he’d have been 40% over when he started driving.

 

 

[FSM]

There is a limit, or there isn’t. Bullshit science. Only proven is the level when the test is done. If he was under he should walk.

Agree he’s lied about his consumption. 2 pints the night before would be undetectable. But if he drank 2 pints just before driving levels could be on the way up, not down.

Edited February 26, 2022 by FSM

[John Wright]

2 minutes ago, FSM said:

There is a limit, or there isn’t. Bullshit science. Only proven is the level when the test is done. If he was under he should walk.

There is a limit. But the law says that whether you are over is mainly calculated when you blow in the police station. But that isn’t when you were driving. Back calculation is used quite often to estimate level at time of driving.

Im not saying it applied in this case, but, from experience, situations like

post driving consumption

smell of alcohol on breath after an accident but blowing just below

where there’s a delay

where the driving has been some distance, especially if there’s been a report of poor driving or where the explanation of when the last drink was ( and how much ) are implausible.

To blow 30, at, say, 10.30 am, with the last drink at 30 minutes past midnight, suggests a reading of 180 just after the last consumption. That’s health endangering level for many people. More likely to have been a morning drink.

Those are the working assumptions, I’d expect.

[FSM]

19 minutes ago, John Wright said:

There is a limit. But the law says that whether you are over is mainly calculated when you blow in the police station. But that isn’t when you were driving. Back calculation is used quite often to estimate level at time of driving.

Im not saying it applied in this case, but, from experience, situations like

post driving consumption

smell of alcohol on breath after an accident but blowing just below

where there’s a delay

where the driving has been some distance, especially if there’s been a report of poor driving or where the explanation of when the last drink was ( and how much ) are implausible.

To blow 30, at, say, 10.30 am, with the last drink at 30 minutes past midnight, suggests a reading of 180 just after the last consumption. That’s health endangering level for many people. More likely to have been a morning drink.

Those are the working assumptions, I’d expect.

I know. But back calculations only usually used in the UK in cases of death or serious injury or if defence of post incident consumption invoked.
Assumptions are just that. Defendant clearly lied about his consumption so all assumptions and consequent calculations should be invalid.

If he had 2 pints just before driving and lied about it, his levels would be on the way up and might never have reached the limit.

He obviously lied about how much and when he drank so to base a calculation on clearly incorrect information seems suspect at best. Not defending him but to convicions based  on unproven suppositions shouldn’t happen.

 

Edited February 26, 2022 by FSM

[John Wright]

1 minute ago, FSM said:

I know. But back calculations only usually used in the UK in cases of death or serious injury or if defence of post incident consumption invoked.
Assumptions are just that. Defendant clearly lied about his consumption so all assumptions and consequent calculations should be invalid.

If he had 2 pints just before driving and lied about it, his levels would be on the way up and might never have reached the limit.

He obviously lied about how much and when he drank so to base a calculation on clearly incorrect information seems suspect at best. Not defending him but to convicions based  on unproven suppositions shouldn’t happen.

Hi conviction was based on two known facts, which are concrete. No assumptions. What he drank and when hasn’t been taken into account.

Known fact 1. What he blew.

Known fact 2. The rate of elimination. This is scientifically documented after 100s of thousands of tests. It’s a range. The defendant is given the benefit of the doubt by applying the lowest parameter. ( in fact, in the worked example I gave, the alcohol level whilst driving was above the limit whichever parameter is used.

There are no unproven suppositions.

Alcohol goes in very very fast, but eliminates slowly. There’s no way, after 90 minutes, it would still be on the up. If he’d downed the alcohol just before driving, in your theoretical, maximum alcohol would have been 10 or 15 minutes later.

[FSM]

13 minutes ago, John Wright said:

Hi conviction was based on two known facts, which are concrete. No assumptions. What he drank and when hasn’t been taken into account.

Known fact 1. What he blew.

Known fact 2. The rate of elimination. This is scientifically documented after 100s of thousands of tests. It’s a range. The defendant is given the benefit of the doubt by applying the lowest parameter. ( in fact, in the worked example I gave, the alcohol level whilst driving was above the limit whichever parameter is used.

There are no unproven suppositions.

Alcohol goes in very very fast, but eliminates slowly. There’s no way, after 90 minutes, it would still be on the up. If he’d downed the alcohol just before driving, in your theoretical, maximum alcohol would have been 10 or 15 minutes later.

Don’t agree, and neither does official UK guidance https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/915637/220_Alcohol_Back_Calculation_v2.0.pdf

back calculations absolutely do depend on what and when he claims to have imbibed.(which he obviously lied about)

alcohol level may continue to increase for between 30 minutes and 2 hours after consumption.
Chap stopped by police, scared , just had 2 pints, says he had a drink the night before. Clearly lied. Prosecution assumes he drank a lot more than he admits to the night before. Assumption, unproven.

Not denying it’s likely the prosecution is right but standard of proof is beyond reasonable doubt isn’t it?

Edited February 26, 2022 by FSM

[John Wright]

8 minutes ago, FSM said:

Don’ agree, and neither does official UK guidance https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/915637/220_Alcohol_Back_Calculation_v2.0.pdf

alcohol level may continue to increase for between 30 minutes snd 2 hiurs after consumption. Chap stopped by police, scared , just had 2 pints, says he had a drink the night before. Clearly lied. Prosecution assumes he drank a lot more than he admits to the night before. Assumption, unproven.

Yes, and no.

The only evidence of drinking was what the defendant told the police. Small amount and the night before.

Small amount recently it wouldn’t increase over the longer periods quoted.

Larger amount night before it wouldn’t be increasing.

my post makes it clear it’s analysing your scenario.

Admissions by a defendant aren’t assumptions.

The time limit since last drink where back calculation shouldn’t be relied on is one hour. The blown reading was probably at least 50% outside that.

[FSM]

32 minutes ago, John Wright said:

Yes, and no.

The only evidence of drinking was what the defendant told the police. Small amount and the night before.

Small amount recently it wouldn’t increase over the longer periods quoted.

Larger amount night before it wouldn’t be increasing.

my post makes it clear it’s analysing your scenario.

Admissions by a defendant aren’t assumptions.

But if admissions clearly and provably untrue? He could have had ten pints the night before, or two ( or ten) just before driving) His “admission” was a lie. Prosecution chose to assume theformer scenario. If he had a lot just before driving levels would be increasing for up to 2 hours(UK official guidance) back calculation shouldn’t be used if levels may still be on increase.

If prosecution are using his account as gospel, 2 pints night before would be undetectable so clearly not a safe basis to make a calculation?

Edited February 26, 2022 by FSM

[John Wright]

5 hours ago, FSM said:

But if admissions clearly and provably untrue? He could have had ten pints the night before, or two ( or ten) just before driving) His “admission” was a lie. Prosecution chose to assume theformer scenario. If he had a lot just before driving levels would be increasing for up to 2 hours(UK official guidance) back calculation shouldn’t be used if levels may still be on increase.

If prosecution are using his account as gospel, 2 pints night before would be undetectable so clearly not a safe basis to make a calculation?

Do you understand the caution? If he says something and then tries to say something different in court the court will probably disbelieve him.

So, yes, he’s stuck with his admissions.

You're clutching at straws.

It looks to me to be a good example of the operation of Duty Advocate for Dummies/Law for Police Station advisers 101 rule 1. Never advise your client to say anything unless it improves his position.

If he’d said nothing, about how much, and when, back calculation would have been impossible, because then it would have been based on assumption and speculation.

 

[FSM]

1 hour ago, John Wright said:

Do you understand the caution? If he says something and then tries to say something different in court the court will probably disbelieve him.

So, yes, he’s stuck with his admissions.

You're clutching at straws.

It looks to me to be a good example of the operation of Duty Advocate for Dummies/Law for Police Station advisers 101 rule 1. Never advise your client to say anything unless it improves his position.

If he’d said nothing, about how much, and when, back calculation would have been impossible, because then it would have been based on assumption and speculation.

 

Yes I understand. 
But his admission was proven untrue by the prosecution’s own expert, so should be disbelieved anyway. To then use that admission as a basis for “proving” him guilty seems wrong to me, but I’m not a lawyer.

Not clutching at straws but I’m with Mr Bumble on this one.

[wrighty]

Long, long time ago now, I was breathalysed after two pints. Under the limit, so sent on my way.  Why was this guy even taken to the station for more tests and calculations? Must be more to his behaviour, or his crash was considered to be due to driving dangerously?

[Gizo]

only going to be more of this when someone had a spliff about a week previously and the Bastard Squad start banging them up for drug driving.