Mr. Gresham Cookeasked the Secretary of State for the Home Department what study he has made of the evidence sent to him by the hon. Member for Twickenham tending to show that breath alcohol tests can give spuriously high results for as long as 30 minutes after the consumption of alcohol; and whether arrangements will he made to instruct the police fully about this aspect of the matter.
§ Mr. Roy JenkinsAuthoritative investigations have shown that traces of alcohol in the mouth do not ordinarily persist after 20 minutes from the time of drinking. I shall advise the police that this is the minimum time which should elapse between a roadside breath test and the offer of a second test at a police station.