Scottish Government

Table 22

(a) Accidents which involved motor vehicle drivers or riders with illegal alcohol levels
Years: 1995 to 2005

(b) Casualties in accidents which involved motor vehicle drivers or riders with illegal alcohol levels
Years: 1995 to 2005

Drink-drive accidents and casualties

Drink-drive estimates: background

1. Each year, the Department for Transport (DfT), estimates the numbers of injury road accidents involving illegal alcohol levels (i.e. above the current drink-drive limit of 80 milligrams (mg) of alcohol per 100 millilitres (ml) of blood). DfT publishes its estimates for Great Britain as a whole in an article in its " Road Casualties Great Britain" statistical volume. Although that article does not provide separate figures for Scotland (or for other parts of Great Britain), DfT produces them as part of its calculations, and these appear in the table below. Because of the uncertainty involved, each estimate is rounded to the nearest ten. The totals, and the annual averages for the five-year periods, have been calculated from the unrounded estimates, and then rounded to the nearest ten.

2. The basis of the estimates is described in the DfT publication. Briefly, they use information from the Road Accidents statistical returns about the numbers of injury road accidents in which one (or more) motor vehicle drivers or riders refused to give a breath test specimen or failed the breath test (by registering over 35 micrograms per 100 millilitres of breath) and information from Procurators Fiscal (and Coroners in England and Wales) about the blood alcohol levels of road users who died within 12 hours of being injured in a road accident. These two sets of information must be used because, for example, some drivers are too seriously injured to be breath tested. The calculations are intended to produce estimates which include allowances for the numbers of cases (e.g.) where drivers or riders were not breath tested because they left the scene of the accident, or where their blood alcohol levels were not reported, for example because they died more than 12 hours after the accident.

3. Estimates for 2006 are not yet available because of the timing of the provision of the results of the blood alcohol tests to DfT.

4. There are no estimates for Scotland of the number of alcohol-related injury road accidents which involve legal alcohol levels (i.e. alcohol levels up to the current drink-drive limit of 80mg of alcohol per 100ml of blood), nor are there any estimates for Scotland of the numbers of non-injury ("damage only") road accidents involving illegal alcohol levels.

5. The figures given here differ from the numbers of drivers with positive (or refused) breath tests. While the Police aim to breath test all drivers involved in an accident, wherever possible, they cannot do so in some cases (for example, hit and run drivers, or where they cannot administer a breath test due to the nature of the injury). In recent years, around three fifths of motorists involved in injury road accidents in Scotland have been breath tested.

Table 22 Accidents which involved motor vehicle drivers or riders with illegal alcohol levels ⁽¹⁾, by severity of accident; and casualties in such accidents, by severity
Years: 1995 to 2005, 1994-98 average and 2001-2005 average
Estimated numbers, adjusted for under-reporting ⁽²⁾

(1) above the current drink-drive limit of 80mg of alcohol per 100ml of blood.
(2) see the explanatory note 2 above.