Police have expressed concern over smart motorways, saying they will make it more difficult to catch dangerous drivers.
Senior officers have warned that the lack of an emergency lane will mean it is impossible to pull over problem drivers.
David Blundell, who leads on roads policing for the Police Federation, said: “The difficulty with smart motorways is that they are difficult for the police to operate on, there’s no hard shoulder, so where do we safely stop another motorist if they have committed an offence or we want to give them some advice?
“The answer is we can’t and we have to wait miles and miles and miles until we’re able to do that. There are lots of questions that need to be asked.”
Large stretches of Britain’s motorway network is being upgraded with new technology intended to improve traffic flow and ease congestion.
Among the initiatives being rolled out is the removal of hard shoulders from around 300 miles of the busiest stretches.