The Departmental Committee on the Regulation of Motor Vehicles announced in 1920 that "a compulsory and uniform code of signals for all road vehicles is to be brought into operation". Drivers in
London had evolved a system for signalling their intentions to turn right or stop, using their arm, and this was seen to be of such benefit that it should be required and standardised as a code of behaviour across the country. The code allowed the driver to use either their own arm or a dummy arm – which had obvious benefits in wet weather for drivers with the luxury of an enclosed cab, or for drivers using left-hand-drive vehicles, as in imported American cars. The intention to bring in the compulsory code was delayed and in successive years the code was expanded including whip signals for horse-drawn vehicles, and signals made by policemen controlling junctions. In 1923 a booklet costing one
penny was published by
His Majesty's Stationery Office and approved by the
Home Office and
Scottish Office. Entitled
Traffic Signals to be used by the Police and Drivers of Vehicles, this booklet arose from discussions between the Police and
The Automobile Association. In subsequent years, in addition to being promoted by the automobile associations, the code was publicised using posters by the National Safety First Association (which still continues this work, having been renamed the
Royal Society for the Prevention of Accidents in 1936). The formal introduction of
The Highway Code was one of the provisions of the wide-reaching
Road Traffic Act 1930. Costing one penny, the first edition of the code was published on 14 April 1931. It contained 21 pages of advice, including the arm signals to be given by drivers and police officers controlling traffic. The second edition, considerably expanded, appeared in 1934, and included illustrated road signs for the first time. During its preparation the
Ministry of Transport consulted with the
Pedestrians' Association. Further major updates followed after the Second World War, references to trams, for example, being removed after the 1954 version. (
Blackpool was for decades the only place in the UK with a tram system. Tramway rules returned to the Code in 1994, after the first modern tram systems in Britain had opened). Motorway driving was first included in the fifth edition. The sixth edition, in 1968, used photographs as well as drawings, and updated the illustrations of road signs to take the new 'continental' designs into account. The 70-page 1978 edition introduced the
Green Cross Code for pedestrians, and orange badges for unskilled drivers. The book's layout was changed to a taller format in the 1990s. An electronic
Highway Code app followed in 2012. Following public consultations in 2020, a new "hierarchy of road users" was incorporated into the 17th edition (2022), classifying road users according to their risk (for example of them being injured) in the event of a collision, with the most vulnerable at the top. == Hierarchy of road users (2022 edition) ==