Cocaine

How cocaine works in your body

Cocaine is a central nervous system stimulant with blocks the reuptake of dopamine and noradrenaline and serotonin. It is metabolised to benzoylecgonine (BZE) which is also tested for under the drug driving legislation but also ecgonine methyl ester both are produced in the liver.

The effects of cocaine are short acting but will depend on the dosage.

Acute intoxication

Acute intoxication can lead to extremely serious and life threatening symptoms:

• Increased heart rate
• Sweating
• Significant pupil dialation
• Increased body temperature
• Loss of appetite
• Reduced need for sleep
• Impact of sexual performance
• Eczema
• Damaged nose.
• Weight loss and malnutrition

In the most severe cases it can present as a condition known as excited delirium syndrome. The is demonstrated by heightened activity and volatility, attraction to bright lights, stripping off to get cool often breathing rapidly and sweating profusely, making no sense and tolerant of pain and excessive strength. Many of these can be caused by medical conditions such as diabetic hypoglycaemia, heat stroke and psychiatric conditions which make it difficult to diagnose.

Death can occur rapidly due to convulsion, intracranial haemorrhage, respiratory arrest ro cardiac arrhythmias.

These risks increase if used with alcohol.

Psychological impact

These are the reasons why people start to use cocaine :

Euphoria which gives you a sensation of increase a physical and mental well being but followed quickly by irritability, depression and insomnia as well as paranoia.

Heavy users can become more tolerant and use up to several grams a day.

Withdrawal when severely addicted can be very painful and addicts often “crash”.

Prescribed cocaine

Cocaine was used as a surface anaesthetic in ear nose/throat surgery but this is now rare.

If cocaine is prescribed a driver would have the statutory defence available to him.

There is a defence has been introduced under S5A(3) of the Road Traffic Act 1988 which states that if a drug is prescribed for medical or dental reasons and taken in accordance with any directions by the Doctor, Dentist or consultant and also the manufacturers instructions. The drugs must also be being used legally ie not prescribed to another.

Cocaine and Driving

Cocaine has a half-life of 0.7 -1.5 hours after which time to get the same effects the dose would have to be repeated every 20 minutes or so.

The onset of the effects will depend on the way in which the drugs were administrated. When sniffed the effects are felt within a few minutes and last up to an hour, if smoked or injected the effects are immediate and will last about 15 -30 minutes.

The typical does is about 100 – 200 mg

The early symptoms of driving will have the following effects:

• Higher Risk taking: pulling out in front of vehicles, taking dangerous overtakes, driving faster
• Poor judgement: impulsive behaviour –behaves erratically when confronted with a dangerous situation.

These heightened symptoms only last a short period of time and then the after effects will kick in and these lead the following issues:

• Slower reaction time – greater distance will be travelled before reacting and there there is a increase risk of a collision.
• Lack of coordination – inabilaity to manage vehicle when driving and react appropriately to an emergency.
• Reduced concentration - miss road signs – traffic lights
• Decreased vision – “snow lights” which affect your periphal vision is common place with cocaine users which means that a driver can miss signs, fail to see pedestrians and other road dangers.

Studies have shown that all users report serious lapses in concentration and ignoring stimuli such as traffic lights.

One study of addicts showed a slower reaction time than non -dependent users which was still evident 3 months after stopping the use of cocaine.

The legal limit for Cocaine

The Govt introduced specific legal limits for both illicit and prescribed drugs in March 2015 when the offence of driving above the specified limit for drugs was introduced.

The specified limit for Cocaine is 10ug. This is a measurement that is 10,000 fold lower than the analysis for alcohol and the analysis is not subject to the type approval or a presumption that the result is correct. This leads to greater uncertainty in results.

The government did not accept the recommended levels which were set in the Wolff report. The report recommended that the level for Cocaine should be 80ug at which they determined a driver would be impaired.*2

Defences for driving over the legal limit for cocaine

Laboratories have struggled to effectively analyse blood samples. There have been two laboratories recently which have lost their accreditation due to errors in their analysis of blood samples. Approximately 4,000 cases have been re-opened and convictions set aside as a result.

It is not a perfect science and you cannot assume that the prosecution analysis is 100% accurate it isn’t.

In recent cases we have experienced issues in blood analyses for cocaine and BZE with one toxicologist pointing out the levels of cocaine and BZE were inconsistent with each other and in order to present these corresponding levels our client would have to have been dead, which fortunately he wasn’t. In fact it was an example of cross contamination at the laboratory.

What to look for?

There a number of tell tale signs in the analytical data pack (ADP) which would indicate the result are unreliable.

• Has the laboratory deducted the 20% allowance from the result – this is the allowed margin of error. If not then your result may be below the specified level.
• Does the laboratory have the proper accreditation which is the validation process which examines their processes to ensure their accuracy in analysing blood samples. There is an accepted 30% allowance between laboratories. Such an allowance suggests that if another laboratory tested the same sample it could come back 30% lower and that is difficult to challenge.
• Poor labelling and lack of continuity. All vials must be labelled correctly and followed through the analysis sometimes this gets muddled up and the prosecution cannot prove that the sample tested was the defendants.
• Has the data input been accurate if there is a “data anomaly” it will usually lead to inaccurate results.
• Failings in the quality control sample – each batch of samples must have a control sample to be measured against if this is contaminated in any way the whole batch would usually need to be re-tested but usually isn’t. Such contamination would lead to higher results and render the results unreliable.
• Have they calibrated the results and equipment accurately. The laboratories must test and calibrate their analytical instruments daily. These results must fall within a recommendation range or standard deviation. These are resulted in the form of graphs on the ADP which can be examined and the deviation checked to see if they fall within the recommended range if not the batch should have been re-tested because the results will not be reliable. Laboratories seldom re-test because it is not profitable to do so their margins for profit are so small.
  

Procedural Issues

The prosecution must follows the procedure to the letter, there include:

1. Compliance with S15 Road Traffic Offenders Act 1988 which specifies how blood samples should be taken and what should be done with them after.
   https://roadtrafficdefencelawyers.co.uk/2023/03/14/the-importance-of-keeping-your-blood-sample-taken-by-the-police/
2. Lack of continuity of the sample. The police must be able to show that the sample tested was your sample and failure to label correctly can break the continuity and offer a defence.
3. Failure to disclose evidence which will assist the us as the defence or undermine the prosecution case. The prosecution often fail to serve evidence within a specified period of time and this can lead to arguments to exclude vital prosecution evidence such as the expert report.

Post Driving Consumption

Many drivers say that when the police are indicating them to stop driving, they panic because they are in possession of some cannabis so having stopped their vehicle and before the police reach them they eat the cocaine.

This is a defence but we would have to prove this on a balance of probabilities. We would have to show that but for the cocaine eaten you would have been under the limit. If done successfully you would be found not guilty and your case would be dismissed.

The police may have body worn video evidence which will either show that you may have taken cocaine or had the time to take cocaine. Equally it may also show that it was impossible for you to take the cocaine.

You will usually need expert evidence to show that but for the cocaine taken after driving you would not have been over the limit.

If you have taken drugs after being stopped then you should tell the police. It makes the argument of post driving consumption more believable.

Special reasons and cocaine

Special reasons can be argued where you have unwittingly taken cannabis in order to avoid the mandatory minimum 12 months ban.

• Medication containing cocaine - some medications may contain cocaine and this can be examined by one of our experts. It may also be applicable if you had surgery recently. Remember unless prescribed this will not be a statutory defence. You would have had to be unaware that you had taken cocaine.
• Laced drinks - usually you would have get the lacer to give evidence or provide some evidence to show that your drinks were laced. You would also have to produce expert evidence to show that but for the lacing element you would have been under the limit. This is easier to establish if you do not use drugs at all.
  

Reference

1. Symptoms and Signs of Substance Misuse 3rd edition Margaret Stark, Jason Payne-Jamesm Michael Scott-Ham
2. Wolff Report 2013