From MPs to GPs, reality TV contestants and even teachers, it seems that anyone in public life can be made to fear for their survival. What’s behind the abuse – and how can it be stopped?

When Jon Burke went into local politics in 2014 he never imagined there would come a time when he considered carrying a rolling pin hidden inside his raincoat when he left the house – “just in case someone jumped out of a car at me with a wrench”. But his mind turned to raiding his kitchen drawers for protection last September, after Hackney council officials called him to say they had received a handwritten letter that threatened to burn down his house while he was sleeping and hurt not just him, but his wife and children.

His crime? Trying to make Hackney a better, safer place – in his eyes – to walk or ride a bike, via the introduction of low traffic neighbourhoods. As the London borough’s cabinet member for transport, Burke found himself at the centre of a row that had become part of the culture wars in which four wheels were pitted against two. The anonymous letter writer made clear they were a car driver: “You fucking cunts ride a bicycle,” they observed.