Data held by the Ministry of Justice relate only to the number of screening breath tests taken for alcohol and the number positive or refused. The available information is given in the following table. Information is not collected centrally on subsequent evidential tests for alcohol.
Tests for drug driving can only be taken using a device of a type approved by the Secretary of State. No type-approved devices are yet available. Figures are not collected centrally on the tests which police carry out for impairment which may be due to a drug. These tests do not involve the use of specialist equipment.
Total number of tests Police force area 2004 2005 2006 Avon and Somerset 27,300 22,000 15,800 Bedfordshire 7,800 6,700 3,100 Cambridgeshire 12,300 12,500 12,500 Cheshire 20,200 22,000 35,700 Cleveland 8,100 10,800 11,300 Cumbria 8,400 13,600 13,800 Derbyshire 31,000 17,700 16,000 Devon and Cornwall 10.700 10,400 13,600 Dorset 7,000 7,900 8,700 Durham 6,100 7,700 6,900 Essex 25,300 34,200 28,400 Gloucestershire 7,100 9,100 10,100 Greater Manchester 19,900 18,900 18,100 Hampshire 38,400 38,300 34,800 Hertfordshire 7,300 11,900 12,700 Humberside 5,600 5,700 10,000 Kent 32,000 31,200 31,700 Lancashire 10,200 13,000 16,400 Leicestershire 115,800 14,400 10,000 Lincolnshire 11,300 11,400 10,600 London, City of 700 1,100 1,600 Merseyside 5,000 8,000 10,600 Metropolitan Police 61,500 67,500 65,000 Norfolk 4,800 10,400 7,800 Northamptonshire 3,200 5,200 4,300 Northumbria 9,800 9,300 7,900 North Yorkshire 8,600 9,300 10,100 Nottinghamshire 8,200 7,900 7,200 South Yorkshire 6,500 13,700 10,300 Staffordshire 13,700 14,300 12,700 Suffolk 10,600 8,900 9,100 Surrey 9,500 9,600 8,300 Sussex 15,200 18,000 18,700 Thames Valley 15,400 14,600 13,500 Warwickshire 5,500 4,800 4,500 West Mercia 8,000 8,800 11,300 West Midlands 6,600 6,900 6,200 West Yorkshire 16,900 15,400 18,000 Wiltshire 7,400 7,200 8,700 Dyfed-Powys 6,700 6,900 7,300 Gwent 1,600 2,000 1,700 North Wales 24,200 21,800 19,600 South Wales 16,700 16,300 17,100 Total 578,000 607,400 601,600 1 Revised since publication of ‘Motoring Offences and Breath Test Statistics, England and Wales, 2004’ bulletin. Note: Every effort is made to ensure that the figures presented are accurate and complete. However, it is important to note that these data have been extracted from large administrative data systems generated by the courts and police forces. As a consequence, care should be taken to ensure data collection processes and their inevitable limitations are taken into account when these data are used.