Drug Seizures by Scottish Police Forces, 2010-11

4. Notes on Statistics used in this Bulletin

4.1 This is the first time since June 2008 that information on drug seizures made by Scottish police forces has been published by the Scottish Government. Prior to this, the Scottish Government had published statistics on the drug seizures made by Scottish police forces twice before. These publications contained data from 1996-97 to 2006-07. Historically the Home Office collected and published the data. The Home Office collected police data from the Scottish Police forces until March 2006.

4.2 The statistics in this bulletin and accompanying tables relate to the seizure of drugs controlled under the Misuse of Drugs Act (MDA) 1971, which came into force on 1 July 1973. The Act divides drugs into three categories according to their harmfulness. A full list of drugs in each category is given in Schedule 2 to the Misuse of Drugs Act 1971, as amended by Orders in Council.

4.3 This bulletin does not contain information from HMRC, British Transport Police and seizures outwith Scotland as a result of Scottish Crime and Drug Enforcement Agency (SCDEA) operational activity. SCDEA seizures in Scotland are included in the police force data included in this bulletin. It is not possible to distinguish which seizures had SCDEA involvement.

4.4 Seizures involving more than one drug are counted as a single seizure in the total number of seizures, but are counted separately against each individual drug or drug class involved. As a seizure can involve more than one drug, figures for individual drug classes cannot be added together to produce totals. Therefore the number of seizures of drug by class can add up to more than the total number of seizures.

For example, if in a single seizure quantities of cocaine, heroin, herbal cannabis and ketamine were seized, the number of seizures would be as follows:

Overall it would be counted as one seizure. In terms of the different classes of drug it would count as one seizure of class A drugs, one seizure of class B drugs and one seizure of class C drugs. Finally, in terms of the different types of drugs it would be counted as one seizure each of cocaine, heroin, herbal cannabis and ketamine.

4.5 A seizure is the result of an operation that is recorded by the police. If the operation undertook raids on several properties this will be recorded as one seizure. Similarly, a single seizure may result in multiple offences and multiple perpetrators.

4.6 Accurate information about drug seizures may take up to nine months to be processed depending on the complexity of the operation and other operational factors. Also, as operations continue, updated information may be available at police force level. Inevitably, the data in this bulletin provide a snap-shot of what the police have recorded at a given time. The definitive number of seizures and quantities recovered at police force level are held by individual forces

4.7 Drugs can be seized in a variety of forms or preparation types. In Tables 5, 6 and 7 quantities of drugs have been converted to weights (kg), liquids (litres) or tablets (000s). To present all seized quantities within a given drug type in terms of one comparable unit, conversion factors are applied to estimate the overall quantity for that drug.

4.8 A number of changes to drug classifications have occurred during the time period relating to this publication.

• Figures for class B drugs include mephedrone and other cathinone-based drugs, which became controlled drugs in April 2010.
• Figures for class C drugs include GBL, 1,4-Butanediol, oripavine and BZP, which became controlled drugs in December 2009.

4.9 Although care is taken in completing and analysing the returns used to compile the figures in this bulletin, the figures are subject to the inaccuracies of any large scale recording system involving different organisations. In order for the reliability of the data to be ensured, a reconciliation exercise was conducted where each police force was asked to check their own data and supply revised figures where necessary during the data analysis stage of this publication.

4.10 Not all drugs that come into the possession of the police have been "seized" in the strictest sense of the word. For example, a member of the public may hand in what appear to be drugs that have been found in the street. These items will be recorded at individual police stations and then destroyed.

4.11 Lothian and Borders Police were unable to provide seizure numbers and quantities, where applicable, for the following types of drugs: methylamphetamine, morphine, barbiturates, anabolic steroids, GHB, ketamine, other benzodiazepines and 'other class C drugs'. This is for logistical, procedural and operational reasons.

4.12 The figures in the tables in this bulletin are generally shown to one decimal place in order to provide a comprehensive record of the information collected. However, the figures are not necessarily accurate to the last digit shown. In some tables components may not add to totals (or the total) because they have been rounded independently.

4.12 The following symbols are used throughout the tables in this bulletin:

- = denotes nil figure or too small to display.

NA = denotes figure is not available.

4.13 Under the Code of Practice for Official Statistics, the estimated costs of responding to statistical surveys and data collection are to be published.

The estimated cost of compliance for supplying and validating the data for this bulletin is: £300.

Details of the calculation methodology are available on the Scottish Government Crime and Justice website at: www.Scotland.gov.uk/Topics/Statistics/Browse/Crime-Justice/costcalculation