The number of dedicated traffic police officers has fallen by nearly a third in 10 years, according to newly-released figures.
All 45 territorial police forces were asked by the Press Association how many dedicated traffic officers they have compared with five and 10 years ago. In 2007 there were 3,766 traffic officers in the 30 forces which responded. In 2012 that figure stood at 3,472 and by 2017 it had dropped to 2,643.
Experts have questioned how new laws, such as the ban on using mobiles while driving, can be enforced with 30% fewer officers dedicated to policing roads.
The AA said the decline could see more drivers getting away with crimes, with a spokesman saying: "We need more cops in cars, not fewer."
Labour's shadow minister for policing and crime Louise Haigh, a former special constable, said: "These savage cuts will deeply alarm the public as reckless drivers will feel able to offend with impunity."
The Home Office said effective road policing is not just dependent on dedicated traffic officers, while the National Police Chiefs' Council (NPCC) pointed out that all officers were able to help traffic specialists.
Gwent saw the biggest drop, from 94 traffic officers in 2007 to none now. Northamptonshire dropped 83% with nine dedicated officers currently compared with 52 in 2007.
Gwent said it had amalgamated traffic officers into "multi-skilled roles" while Northamptonshire said it had "regionalised" its road traffic officers.
Hertfordshire, Northumbria, West Mercia, Surrey and Sussex were the only forces to increase numbers.
Jason Wakeford, from road safety charity Brake, said the Government and police forces "have to start treating road policing as a national priority and reverse the savage cuts to officer numbers".
Jayne Willetts, of the Police Federation of England of Wales, said cuts meant specialist roads policing officers now face added demands, adding: "Unfortunately the thin blue line is becoming too thin."
West Mercia Chief Constable Anthony Bangham, who speaks on roads policing for the NPCC, said: "Individual police forces decide how best to allocate resources and keep their communities safe.
"Some may choose to reduce the numbers of specialist traffic officers, but this does not mean that their roads are not adequately policed.
"They can deploy a range of resources, including ANPR (Automatic Number Plate Recognition) technology, targeted patrols using unmarked vans, high vantage points and helmet cams to catch offenders."
The Home Office said deployment of resources was a matter for chief constables and crime commissioners, who "understand their operational needs better than anyone".
A spokesman said: "The Government has protected overall police spending in real terms since the Spending Review 2015 and we will always ensure forces have the resources they need to do their vitally important work.
"Effective roads policing is not necessarily dependent on dedicated road traffic officers: the use of technology, other police personnel and local communities also have a role to play."