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HMRC internal manual

Oils Technical Manual

Law - background: the interpretation of UK law


UK legislation is published at

As legislation does not remain static and may be amended by subsequent legislation, in order to ensure that copies of the Acts and Regulations which you are using are the most up-to- date, you will need to refer to the current version of the Purple Book (Customs & Excise Duties) 3A and 3B which are issued to all Excise Policy teams and to most LB/Excise Compliance staff. Staff dealing with oil imports will need to refer to the Purple Book 3A, which covers import regulations, or to the Tariff. As the law forms the basis of our oils assurance activities, it will often be necessary to refer to the full legislation and to any subsequent amendments that may have been made to this.

If you have any doubt as to any legal position on oils, please contact the Policy Team.

Contacting the Fuel Duties Policy Team

For details on how to contact the Policy Team please see HCOTEG10770 in the ‘Introduction and overview of oils activity’ section of this guidance.

How does the law get interpreted and what happens if there is a disagreement?

That a law may need interpreting might seem odd, but as has been mentioned, we often use our existing powers and the existing legislation in order to do new things. As a result, there may then be some ambiguity in the interpretation of the law, as it has not been used solely for the purpose(s) for which it was originally intended.

For example, excepted vehicles can use rebated fuel, but when is a truck an ‘excepted vehicle’? Should a truck be considered a ‘road construction vehicle’ and hence entitled to use rebated ‘red’ diesel or as simply a ‘truck’ which must use fully duty paid ‘white’ diesel instead?

There may also be advances or developments, which could not have been anticipated at the time the law was passed. For instance, where an agricultural tractor used to be only for ploughing fields and for moving things around slowly, now tractors can travel at 60 mph; whereas road haulage trucks can no longer do this- as many now have a restrictor fitted by law which limits their speed to 56mph.

N.B. Whilst there is advice on ‘excepted vehicles’ on the intranet, this is an area where there is constant ambiguity in the interpretation and application of the law, and one upon which the Policy Team should be consulted, and will give advice.