Video report by ITV News Correspondent Rupert Evelyn
A government review into smart motorways has been completed and will be published shortly, ITV News understands.
The families of victims who have been killed along stretches of smart motorways have called on the government to scrap them.
The review is expected to back the continued use of smart motorways - worrying those who believe they are dangerous.
Smart motorways differ in form, but can involve the hard shoulder being turned into an additional lane to reduce traffic.
Meera Naran's eight-year-old son, Dev, and Claire Mercer's husband, Jason, died in separate incidents on roads where the hard shoulder can be opened and turned into an extra lane to reduce traffic.
Dev Naran was killed when a lorry smashed into the back of the car in which he was sat, parked in what would have been the hard shoulder, but which had been opened to traffic.
Mr Mercer died after being hit by a lorry on the M1. He was also on a section of the motorway where there was no hard shoulder available.
Campaigners say smart motorways increase the risk of injury or death to those who have broken down on the motorway, as it often leaves drivers with nowhere to pull over.
Unless you get into a refuge area, there are questions as to where you can park if you do need to stop.
Fighting back tears, Ms Mercer told ITV News: "You don't want police knocking at our door because you know what they're going to tell you. I didn't even know what a smart motorway was, I didn't even know they existed."
Ms Naran said: "We don't want anyone else to go through this. We don't want anyone else to feel this pain."
RAC head of roads policy, Nicholas Lyes, also raised concerns about the roll-out of smart motorways.
He said: "The risks associated with this increase when a vehicle slows down and can't make it to a refuge area.
"That vehicle that is in that position is at a higher risk of being involved in a collision than it would be if there was a hard shoulder."
Highways England said it is supporting the government to establish facts around smart motorways and that their own findings show increased safety levels.