Criminal cases involving the possession, sale, manufacture and importation of drugs in the UK are governed by two main pieces of drug legislation:
This act divides controlled drugs into three classes A, B and C ostensibly, on the basis of perceived harm. Class A drugs are perceived as the most harmful and are therefore linked to the most punitive penalties. Class C drugs are perceived as being the least harmful and are therefore linked to the least severe penalties. A full list of Illegal substances and the sentences they carry can be found here.
In recent years many new drugs have been added and continue to be added to the Misuse of Drugs Act 1971 in the form of amendment orders. Drugs that were so called ‘legal highs’ (i.e. which were abused recreationally, but could legally be bought and used in the UK) can be quickly added to the Act by means of the Home Secretary invoking a temporary class drug order. This order comes into effect immediately after parliament has agreed it and lasts for up to 12 months.
However, this ability to amend effectively obviates the need for having to prove a particular drug is harmful. In theory if a drug is added temporarily and is later proved not to be harmful it could be removed from control, although in practice this is unlikely to happen.
It is therefore possible that someone could have purchased drugs when they were not controlled. But then subsequently have them seized by police after they have become controlled and would therefore be charged under the Misuse of Drugs Act.
Because there are many variants of drugs, they are controlled on mass, based on their chemical structure, rather than by naming them specifically. This can make ascertaining whether certain new drugs are controlled or not quite difficult unless, one is a forensic drugs expert with the ability to undertake independent drugs comparisons and purity analysis.
These require no prescription and may be sold in a wide range of shops. They would include things like low strength paracetamol tablets, cold medicines, vitamins and herbal remedies.
These may only be sold in pharmacies and a pharmacist must make or supervise the sale. They would include things like nasal decongestants and antihistamines. In addition, some pharmacy medicines may only be sold if the pharmacist is satisfied that the person buying the medicine meets certain medical criteria.
These medicines may only be obtained from a pharmacist upon presentation of a prescription from a GP, dentist or other registered healthcare professional. It may be possible to obtain some prescription medicines for personal use via the internet from overseas, but anybody who is not a registered healthcare professional who then seeks to sell them onto others, will be contravening the Medicines Act 1968 and can be prosecuted on that basis.
Some Prescription only medicines (POM) are also controlled under the Misuse of Drugs Act (MDA) 1971 (as amended). This means that it is a criminal offence to possess them without a valid personal prescription and it is a criminal offence to sell them to others. These would include preparations like Valium, which contains the drug diazepam, which is a Class C controlled drug under MDA 1971 (as amended).