In the current sexual harassment scandal enveloping Westminster, a spokesman for the Prime Minister was asked whether the PM had seen a dossier listing all the misdemeanours of her MPs. He was quoted in The Guardian as saying: "There is no dossier and therefore the Prime Minister hasn't seen one."
Writing in The Telegraph (paywall), Rob Wilson, a former Conservative whip, says: "The notorious black book of MPs' misdeeds does exist".
Who is lying? Who is speaking the truth? I tend to believe Mr Wilson. Which makes one wonder about the wisdom of Number 10 making a statement which will almost certainly be shown to be false.
The whip system may be one of the most corrupting institutions in the country. Party discipline is enforced through what is euphemistically called a 'carrot and stick' approach. MPs who cannot be convinced by argument to support the government position - or maybe are simply playing hard to get in the hope of favours and career advancement - are alternately cajoled and bribed with promises of career favours. Or perhaps even blackmailed with exposure of the peccadillos listed in the black book. All this famously fictionalised in House of Cards.
For political parties, party discipline is more important than having MPs faithfully discharge their duty to their constituents by making their own judgement about specific pieces of legislation. So whatever it takes to impose discipline is just fine. Conscience and rational argument be damned. If it means keeping unacceptable or maybe even criminal behaviour safely hidden away in a black book for later use, then so be it.
It can well be argued that parliament and government would cease to function if voting became a free for all. After all, most parties are a broad church that try to accommodate multiple views. Some way of imposing order on a herd of cats that have very little in common might therefore be considered essential.
Maybe rather than trying to find ways of treating the symptoms, we can search for the underlying causes. I suggest that our first-past-the-post electoral system, that embeds a two party system, is a significant contributing factor. Anyone entering politics knows that their chances of election and career success are much greater if they join one of the two main parties. They may not have much in common with others in the party. They may, from time to time, even despise the leadership and the party's political platform (cue, today's Labour Party). But there is nowhere for them to go. The result - parties that are impossible to hold together without silencing dissent through bribery or blackmail.
A further problem is that the two-party system kills dead skills of negotiation and compromise - skills that are essential in a proportional system where coalition government is the norm.
Maybe nowhere is this catastrophic failure more visible than in the current Brexit process. Our continental friends must be looking on in bewildered amazement at the shamefully demeaning spectacle of a British government in utter disarray. A government unable to develop any kind of coherence within its own party, let alone lead the country through the most momentous period in its recent history.
Coalition government also tends to encourage cohesion within individual parties. Negotiating as a block with other parties becomes more important than bickering within one's own party.
It is no wonder that Westminster is in shock and panic about the current allegations. Far from being a little local problem, it threatens to bring down the whole fragile house of cards. Yet we know what we can expect. Some kind of inadequate sticking plaster will be found to place on what is a deep, festering wound of cover-up, bribery and blackmail at the heart of our democratic system.