An estimated 6.5 million people in the UK are using CBD products, and yet those selling it say the industry and its consumers are being left in limbo by the current law.
CBD (or Cannabidiol) is a chemical found in marijuana but crucially it does not contain THC, the psychoactive substance in cannabis, which gets you high.
The industry has boomed in recent years, and is now worth around £300 million, according to Prohibition Partners.
But the UK law has been branded "ridiculous" for leaving one CBD product in a legal "grey area".
CBD flower can be smoked, vaped, or made into tea.
It has the same benefits as any other CBD product. It resembles the cannabis flower but, again, has little to no THC in it.
Under the Misuse of Drugs Act, however, all forms of the cannabis flower (regardless of their THC content) are classified as a controlled substance and are therefore, illegal.
That's something George, the CEO of a CBD company in the UK, said is "ridiculous".
"I could have the flower, in its full flower form. I can go like this [crumbles flower] the flower is now crumbled up, legal. I'm not being dramatic. That's how sort of ridiculously confusing the situation is."
The point, he said, is that UK law is too focused on the material itself rather than "the science".
This came to a head last year when the Crown Prosecution Service tried to convict a CBD company that was found importing low-THC flower.
Though the THC content of the flower was below 0.2% (within the legal threshold), the flower itself sits in this so-called legal "grey area," according to suppliers.
The case went to the Court of Appeal, which ruled in favour of the CBD company.
Judges said they did not consider flower with a THC content below 0.2% a "narcotic drug" and so ruled that the company could not have broken the law under the Misuse of Drugs Act.
Indeed, ITV News has seen evidence of several CBD companies selling flower within the UK.
Many suppliers are calling on the government to update the law around CBD products, so that legality is based on psychoactive substances - rather than the material itself.
"So what the EU law states is that any flower with less than 0.2% THC is a CBD flower and, therefore, legal," George said.
"Any flower with north of 0.2% THC is a cannabis flower and, therefore, illegal.
"There's no grey area. It's not confusing, because you’re looking at it scientifically and you’re saying 'at what is the substance psychoactive at that point it’s illegal'."
When we put this to the Home Office, the government did suggest more clarity is needed, a spokesperson said: "CBD, as an isolated substance, is not a controlled drug. We will be providing greater clarity for responsible suppliers by introducing defined limits on the controlled drug content of consumer CBD products".
But on whether that would include a change in the law around the flower itself, a spokesperson said: "The flowers of the cannabis plant are controlled under UK legislation irrespective of THC content. The UK government has no plans to change this legislation".
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