'MUST NOT' vs 'DO NOT' and 'SHOULD NOT'

"Many of the rules in The Highway Code are legal requirements, and if you disobey these rules you are committing a criminal offence. You may be fined, given penalty points on your licence or be disqualified from driving. In the most serious cases you may be sent to prison. Such rules are identified by the use of the words ‘MUST/MUST NOT’."... 

"Although failure to comply with the other rules of The Highway Code will not, in itself, cause a person to be prosecuted, The Highway Code may be used in evidence in any court proceedings under the Traffic Acts (see The road user and the law) to establish liability. This includes rules which use advisory wording such as ‘SHOULD/SHOULD NOT’ or ‘DO/DO NOT’."

(The capitalisation in the last sentence is mine - it really should be added to the Highway Code !)


This may be a large part of the problem : much of  'dangerous' or 'careless driving' is not defined in the Highway Code. Even if it is, police see a lot of dangerous or careless driving and compare it to the Highway Code, concluding "It doesn't say MUST so it's not an offence".

eg Lifting a finger - [ Pedaller ]

"Accordingly the drivers overtaking you in contravention of this rule do not commit an offence per se and so it would not be a matter in which the police would intervene."

eg Driving while blind !

"The court heard Rashid was short sighted, could only read a car registration plate from 7ft (1.5m) away and had admitted to police he had not worn his glasses for a year and did not know where they were."

"The judge said: "I suggest we will never know why you did not see the victim. "It would have been desirable and prudent to wear the specs, but there is nothing unlawful about that. "The only possible aggravating factor is the specs and in evidence we heard they were not a legal requirement."

Perhaps there are cases where the HC should say MUST, but doesn't ?

Perhaps 'Case Law' (Judges' rulings) should prompt the use of MUST - it just seems to be 'Staute Law' (Acts of Parliament) at the moment ! I must find out more about Case Law and Precedent.