A ruling by Finland’s Supreme Court means that motorists will likely not be charged for driving under the influence days after using cannabis.

The influence of cannabis on users dissipates after some hours, however its "fingerprints" remain in the body for even longer. The court ruling aims to recognise that compounds related to metabolising cannabis may remain in the body for days after using the drug, although the user's ability to drive may not be impaired.

In Finland using cannabis is still illegal and drivers are still likely to be charged for the offence if they get behind the wheel hours after indulging in its use.

Cannabis usage leaves a substance known as tetrahydrocannabinol or THC in the body, prompting the production of a metabolite, carboxytetrahydrocannabinol (THC-COOH, where a metabolite is a substance required for or produced from metabolism.

THC is a psychoactive substance, which intoxicates people, so detecting it in a driver’s bold always results in a charge for driving under the influence. In Finland, police generally also issue a DUI citation if they find the metabolite THC-COOH in the blood.

However there is a major difference between the compounds.

Depending on the dosage taken, THC is known to leave the body between six and eight hours after cannabis use. However metabolites like THC-COOH may show up in blood samples for days or weeks longer. It is the equivalent of a cannabis "fingerprint" that reveals use of the drug in the recent past.

Unlike THC, the metabolite THC-COOH does not have an intoxicating effect and therefore does not impair the ability to drive.

According to Teemu Gunnar, a forensic toxicologist with the National Institute of Health and Welfare, THL, it makes sense that identifying THC-COOH in the blood should not automatically lead to a DUI sanction.

"It’s quite rational that finding it several days after use would not lead to a drunk driving penalty because it does not affect the ability to drive," he said.

Supreme Court decision changes police and prosecutor practices

A few years ago the Supreme Court dismissed an appeal court conviction in the case of a driver who had smoked cannabis before getting behind the wheel. THC-COOH "does not affect the ability to drive nor endanger traffic safety even at high levels," the court said in its ruling.

Since that ruling, police and prosecutors have changed their practices to bring them in line with the court’s judgment. Prosecutors no longer press charges solely on the basis of the presence of THC-COOH in the blood, or when the police have confirmed that there is no reason to suspect an offence was committed.

"We have acted in accordance with the Supreme Court guideline, in other words for the most part we do not lay charges. Before [the precedent] it led to charges," noted district prosecutor Tero Kekki.

"We have reacted and practices have changed. So we don’t do any unnecessary work," commented detective inspector Ilpo Pajunen of the Helsinki police department.

In spite of the precedent-setting case, officials have still sanctioned motorists for driving days after cannabis use in the period since the ruling.

The reason for the lag can be found in Finland’s criminal code, which calls for a driver to be cited for DUI if their blood has "an active substance or metabolite of a drug used" during the time they were driving or shortly afterwards.

In its judgment, the Supreme Court noted the need for legislative changes. Preliminary drafts state that the drunk driving offence should not be applied to cases where a motorist’s ability to drive cannot be said to have deteriorated due to drug use.

Increase drug-related in DUIs

Growing numbers of drivers on Finnish roads are people pulled over for DUIs caused by drug use, with amphetamines the substance most commonly detected in these cases. Last year, police reported 5,107 such cases.

Cannabis metabolites were the second-most-frequently found substances. In 2018, records showed 1,784 hits of THC in lab samples and 3,794 of THC-COOH.

Moreover, the majority of blood samples handed over to the National Bureau of Investigation, NBI, contained several intoxicants. From the perspective of the subjects’ ability to drive, the least significant substance is not necessarily THC, but other possible drugs – or even the more traditional alcohol.

Police also said that drivers are sent for drug testing when they feel there is reason to suspect drugs are involved. For example, when the breathalyser registers no alcohol, but driving ability is clearly impaired.

Pajunen said that he suspects that drivers who have used cannabis days before and are then able to manage a vehicle do not end up being tested for drugs.

"There must be some kind of trigger to suspect the influence of drugs. Behaviour, driving mistakes or something like that," he added.

Standard units for grading the potency of cannabis – similar to those already used for alcohol – would result in significant improvements in the mental health of users, according to addiction experts.

Researchers from the Addiction and Mental Health Group at the University of Bath, working with staff from King’s College London, UCL and the Australian Catholic University in Melbourne, say more needs to be done to make people aware of the levels of THC – the main psychoactive component – in the cannabis they are consuming.

Writing in the journal Addiction, the experts suggest a unit level should be set at 5mg of THC – the amount that would typically be found in a small joint. This is enough to induce intoxication but without psychotic symptoms, they say.

“Our findings add to a growing body of evidence that suggests the health effects of cannabis are dose-related,” said lead author Sam Craft, from King’s College London. “We believe a unit system would help both users and healthcare professionals by providing clearer information on the types of cannabis products and their strength.”

Previous research from the team has highlighted how concentrations of THC in cannabis have doubled across Europe in the past decade. But although use of the drug is widespread and there are moves in some countries to legalise it, standard units – which have been commonplace for alcohol for many years – have not been adopted in health guidelines.

The authors believe that a standard unit system would also yield benefits for countries where cannabis use is illegal, such as the UK. “Where the unit system for alcohol has helped consumers to better manage their alcohol intake, so, too, this could have important implications for cannabis users,” said senior author Dr Tom Freeman from the University of Bath. “This should give clear guidance about the dose of THC people are consuming. Our hope is that the introduction of a system in locations where the drug is legalised will have knock-on effects to countries where it is not, providing users and clinicians with an important toolkit to guide safer use.”

The publication coincides with a second study from the team, published in the journal Psychological Medicine, which examines the relationship between cannabis and key health outcomes in more than 55,000 people across 175 countries.

Using the Global Drug Survey, consumers were asked about the types of cannabis they used and their health. The results showed those who used higher THC forms of cannabis, such as hashish, experienced more severe health problems than those using traditional herbal products with lower levels of THC.

A row is brewing between the ACT and Federal Government over controversial moves to legalise cannabis in Canberra from early next year.

The ACT Government last month passed legislation legalising possessing, smoking and growing small amounts of cannabis from early next year.

Adults can possess up to 50 grams of dry cannabis and grow two plants.

The passage of the laws appeared to take many within the Federal Government by surprise, and prompted a strong response, with some senior Government ministers labelling it "crazy" and suggesting the ACT Government was spending "too much time smoking hooch".

Mr Hunt wrote to Mr Barr this week detailing his concerns around the potential health impacts of the legislation, and querying how his Government came to support the private members bill.

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"I have serious concerns the ACT's legislation will result in further health harms and exacerbate mental health issues, particularly for those who have a family history of mental health disorders," he wrote.

"I note that both the Australian Medical Association and the Royal Australian College of Surgeons have also expressed concerns over the legislation, with the latter calling for it to be reversed."

Mr Hunt attached a dossier of research and briefings on both the physical and mental health effects of recreational use of cannabis, to back up his claims.

"I call on you to explain whether the ACT Government considered the international evidence on the health effects of cannabis and to provide any evidence to the contrary," he wrote.

Within the letter, Mr Hunt noted the global direction on regulation of cannabis was towards legalisation and decriminalisation, but he suggested that was prompting more research into its adverse effects.

A spokeswoman for the ACT Government said they intended "to respond fulsomely to Mr Hunt's letter" in the coming days.

The health impacts of the legislation are not the only potential point of conflict between the Federal and ACT Governments over the contentious legislation.

Federal Attorney-General Christian Porter is still considering the legalities of the bill, although the final version of the legislation is yet to be published.

The ACT laws directly conflict with Commonwealth legislation, which prohibits the possession of cannabis.

Mr Porter has not ruled out seeking to have the laws overturned.

Medical marijuana firm AMP German Cannabis Group announced that it will begin auditing its supply chain in accordance with the European Union (EU) Good Manufacturing Procedure (EU-GMP) to "ensure the quality and integrity of pharmaceutical goods" as they move through the supply chain from the supplier to the German patient.

Legalization of medical marijuana in Germany happened fairly recently (in 2017), while recreational cannabis continues to remain illegal. Nonetheless, even with medical marijuana being legal, patients still face significant difficulties in procuring it as Germany contends with supply shortages and unnaturally high shelf prices.

This ultimately boils down to the confusing reality of laws that govern marijuana in Germany. Since marijuana is still classified under narcotics and carries a state prohibition on its growth, sale and distribution, domestic cannabis fields cannot exist in Germany – making patients rely entirely on pharmaceutical imports for their needs. 

Recognizing a huge opportunity, several foreign pharmaceutical companies have taken an interest in importing medical marijuana in Germany. A growing number of doctors jump onto the cannabis bandwagon every year, endorsing cannabis therapies for a variety of ailments, and thus creating a perfect recipe for the medical marijuana supply chain to flourish. 

For AMP, the EU-GMP certification will help push products earmarked to meet the highest consumer health and safety standards. Meeting these standards will also ensure a more effortless entry into the German market. 

"In addition to ensuring the suppliers' production and operating processes meet EU-GMP certification standards, AMP's German pharmaceutical consulting partner will audit AMP's supply chain service providers during the fourth quarter of 2019 to ensure the quality and integrity of the pharmaceutical goods is maintained during transportation, warehousing, handling, testing and distribution," said the company in a statement. 

The idea of EU-GMP certification apart, global cannabis supply chains can also look to leverage the technology of blockchain to bring transparency and visibility into the movement of marijuana from the field to the pharmacy counter. Blockchain can also ensure accountability from every stakeholder across the value chain, as the decentralized ledger technology demands equal participation and responsibility from every party involved. 

Pushing all the stakeholders onto a single decentralized blockchain network will also eliminate possibilities of counterfeit cannabis products making their way into the supply chain. Marijuana cultivation produces a lot of waste and some plants die along the way, which makes it vital to keep an accurate measure on the volume of harvested cannabis to ensure safety. 

AMP expects its first imports into Germany to begin by the first half of 2020. AMP will be procuring its medical cannabis from two licensed producers based in the state of Alberta, Canada. The supply agreements will be made more concrete once these producers clear the audit for EU-GMP certification and receive their sales license from Health Canada. 

AMP will check the medical cannabis products before they are transported from Canada to Frankfurt, Germany, via air freight. Upon landing in Frankfurt, the products will be stored at a narcotics storage facility. The products will be inspected one last time before they are cleared to be sold to German pharmaceutical wholesalers. These wholesalers will only be allowed to sell the stocks to pharmacists who are contractually bound to AMP for their medical cannabis supply – thus ensuring strict accountability over the cannabis inventory.