Just over 500 years ago, Guy Fawkes was found lurking below the House of Lords, with 36 poorly concealed barrels of gunpowder. His intent and that of his 12 co-conspirators was murderous. But their plotting had been foiled by an anonymous letter sent to the 4th Baron Monteagle a week before. They were apprehended, grotesquely executed and Parliament survived unscathed.

To avoid copycat attempts, to this day, before the State Opening of Parliament, a search for bombs in Parliament’s cellars is conducted, by the Yeomen of the Guard, the royal bodyguards. Consistently they return empty-handed from their inspections.

But could it be that they are focusing their attention in the wrong quarters? Should they be devoting more time to scrutinising what is happening above ground rather than below? Would it be wiser to examine what takes place in Parliament's gilded chambers and Pugin-designed meeting rooms, rather than in the labyrinth of dank and musty tunnels that run underneath?

If they did, they’d find an emerging threat to Parliament that is insidious and covert and could rip the heart out of our democracy much more effectively than a large quantity of high explosives. This menace is more of a drip drip drip erosion of Parliamentary rights than a big bang demolition.

It started with the present Prime Minister’s attempt to shut down Parliament, demonstrating his contempt for parliamentary sovereignty.

It gathered momentum with threats to the judiciary.

It quickened when the PM condoned bullying by the Home Secretary and schmoozing by the then Communities Secretary with a Conservative donor.

It accelerated with an Elections Bill that will make it harder for people to vote and destroy the independence of the Electoral Commission.

It reached terminal velocity with Wednesday’s grubby scheming designed to let a Conservative MP found guilty by a cross party of MPs of ‘egregious’ lobbying, off the hook.

We ​don't need​ an anonymous letter to tip us off about what is happening, here and now, in plain sight. We just have to open our eyes.

A PM and a Government with a comfortable majority which believes the rules and conventions don’t apply to them doesn’t ​have to smuggle in sticks of dynamite to wreak havoc on our traditions, rights and values. It just needs a competent team of Government whips and compliant Government MPs. The Government has both.

Tom Brake

Director, Unlock Democracy