Campaigners carried 38 cardboard coffins to Parliament Square to demand a ban on the all-lane running motorways. The action was led by Claire Mercer, whose husband died on a stretch of the M1 without a hard shoulder.
Mr Mercer, 44, and Alexandru Murgeanu, 22, died near Sheffield when a lorry crashed into their vehicles which had stopped on the motorway after a"minor shunt".
"There's a really strong feeling against these. We need to embarrass the Government into actually doing something.Image: Controlled smart motorways have a permanent hard shoulder and use technology to regulate traffic and have the"lowest casualty rates" of all roads across motorways and major A roads in England.
"Smart motorways almost cost me an arm and a leg," he said, describing how his bike slammed against the barrier, causing him to lose"a big chunk" of his leg, shattering his kneecap and dislocating his shoulder."We're all here as receipts from the hidden costs of profits over people," he added.