PROCEDURE FOR BACK CALCULATON IN DRINK DRIVING CASES POLICY REFERENCE 10/287
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
NOT PROTECTIVELY MARKED
Derbyshire Constabulary
PROCEDURE FOR BACK CALCULATON
IN DRINK DRIVING CASES
POLICY REFERENCE 10/287
This procedure is suitable for Public Disclosure
Owner of Doc: Operational Support
Date Approved: July 2010
Review Date: July 2015
1
NOT PROTECTIVELY MARKEDNOT PROTECTIVELY MARKED
INDEX
Heading Page No
1. Procedure Identification Page ......................................................................... 3
2. Legislative Compliance.................................................................................... 4
3. About this Procedure ....................................................................................... 4
4. Risk Assessment and Health and Safety Considerations............................. 4
5. The Procedure .................................................................................................. 4
2
NOT PROTECTIVELY MARKEDNOT PROTECTIVELY MARKED
1. Procedure Identification Page
Procedure title: Back Calculation in Drink Driving Cases
Registry Reference number: 10/287
Procedure implementation date: July 2010
Procedure review date: July 2015
Department / Division responsible: Operational Support
Policy owner: Divisional Commander
Last reviewed by: Sgt. 1952 Brown Date last reviewed: July 2014
Impacts on other policies / guidance / documents (list):
None
Security Classification:
NOT PROTECTIVELY MARKED
Disclosable under FOI Act: YES
Procedure to be published on Intranet YES
Procedure to be published on Force Website YES
Procedure disclosable to public via FOI request YES
3
NOT PROTECTIVELY MARKEDNOT PROTECTIVELY MARKED
2. Legislative Compliance
This document has been drafted to comply with the principles of the Human Rights Act.
Proportionality has been identified as the key to Human Rights compliance, this means
striking a fair balance between the rights of the individual and those of the rest of the
community. There must be a reasonable relationship between the aim to be achieved and
the means used.
Equality and Diversity issues have also been considered to ensure compliance with the
Equality Act 2010 and meet our legal obligation in relation to the equality duty. In addition,
Data Protection, Freedom of Information and Health and Safety Issues have been
considered. Adherence to this policy or procedure will therefore ensure compliance with all
relevant legislation and internal policies.
It is important that high quality customer service is provided as part of the Back Calculation
Guidance and the standards specified in the Customer Service Policy apply throughout this
document.
3. About this Procedure
This document explains the procedure that is followed by Derbyshire Constabulary officers
when obtaining back calculations in relation to breath, blood or urine specimens provided by
persons during investigations into offences under Sections 3A, 4 or 5 of the Road Traffic Act
1988.
The back calculation process is carried out by an expert, qualified in the relevant field, with a
view to establishing the likely alcohol content present in a persons body at a given time prior
to the taking of the evidential breath, blood or urine specimen.
The procedure is carried out for the Derbyshire Constabulary by the Forensic Science
Service.
4. Risk Assessments/Health and Safety Considerations
There are no specific risks associated with the implementation of this procedure.
5. The Procedure
The back calculation process will generally only be used in connection with investigations
into serious injury or fatal crash cases. If a clear case is made in other cases then the
decision to despatch the sample will rest with the Inspector, Roads Policing.
The back calculation process will be used where the analysis of evidential breath, blood or
urine specimens indicates a level of alcohol present in the specimen which is below the
prescribed legal limit but the investigators have reason to suspect at the time of the alleged
incident, that gave rise to the taking of the specimen, alcohol level would have exceeded the
legal limit.
4
NOT PROTECTIVELY MARKEDNOT PROTECTIVELY MARKED
Where back calculation is being considered, for any reason, and the subject’s lower breath
result is less than 51 microgrammes of alcohol in 100 millilitres of breath, the statutory
option to replace the breath specimens with a blood or urine specimen must be given. This
applies even if the alcohol reading is as low as 10 microgrammes of alcohol in 100
millilitres of breath.
The national form MGDD/A explains the legal requirements in note form and directs the
operator to the MGDD/B. This procedure must be followed otherwise any subsequent back
calculation will be invalid and no prosecution for an ‘excess alcohol’ offence will be possible.
The fact that a subject’s lower breath reading is less than 40 microgrammes of alcohol in
100 millilitres of breath does not mean that there is no legal requirement to follow the
statutory option. The statutory option applies to any reading below 51 microgrammes of
alcohol in 100 millilitres of breath, although if the lower reading is below 40 microgrammes
of alcohol in 100 millilitres of breath and there is no intention to carry out any back
calculation, there is no requirement to action it.
If the subject declines the statutory option when offered, then any subsequent back
calculation is based upon the breath specimens provided. If a subject accepts the statutory
option then any subsequent back calculation is based upon the result of the analysis of the
blood or urine specimen provided.
The level of alcohol at the roadside and the result of the evidential test can be used to assist
calculations as to the elimination rate specific to that individual, which in turn may then be
used to assist with a back calculation. If the practices relating to the calibration and handling
of preliminary breath testing devices cannot be verified, or cannot be shown to be accurate,
this could have a very serious effect on any subsequent calculations and possible
prosecution.
In cases where back calculation is being considered the suspected person will, after
completion of Form MG/DD/D in an interview setting, be granted police bail to return to a
police station at a later time and date. A period of eight weeks is normally sufficient time to
allow a back calculation to be completed.
The officer in the case must ensure timely submission of the form to the Forensic
Administration Department at Headquarters. Form MGFFS is not normally needed in these
cases provided the information requires at D3 on the form MG/DD/D is completed in full.
In cases where the result of the back calculation indicates that at the time of the alleged
incident the suspected person had a level of alcohol in their breath, blood or urine which
exceeded the prescribed limit the officer in the case will confer with the CPS and prepare a
prosecution file. When the accused surrenders to their bail they will, except in exceptional
circumstances, be charged with the relevant offence.
In cases where the result of the back calculation indicates that at the time of the alleged
incident the level of alcohol in the suspected persons breath, blood or urine would not have
exceeded the prescribed limit, the officer in the case must arrange for a letter to be sent to
the accused releasing them from their obligation to answer their bail, unless there are other
significant matters that warrant their attendance. If a persons bail is cancelled then
additionally the officer must notify the custody centre where the person was due to
surrender to their bail.
5
NOT PROTECTIVELY MARKEDYou can also read
