It seems fair to say that the Number 10 parties scandal has brought several issues into the spotlight. There is the harshness of the UK’s lockdown rules; the seemingly endless capacity for those in power to regard themselves as above the law; the inscrutable internal mechanics of the parliamentary Conservative Party and so on.

What do they all have in common? Well, none of them would be making headlines now – or getting investigated by Sue Gray – if it weren’t for leaks. After all, the boozy work events took place last year and the year before that; had insiders not decided to start spilling their secrets to journalists last month, we would collectively be none the wiser.

It isn’t possible to know who decided to tattle and why they decided to do so now, but it seems worth taking a broader look at the leaking culture in Westminster, how it works, and what it tells us about how our Britain is being run.

Jigsaw puzzle

“I see it as a jigsaw with some of the pieces missing,” says one senior political journalist. “If you’re lucky, you'll get a big bit – something identifiable – and from that you can extrapolate and build outwards. But mostly what happens is you get the outside bits and have to build inwards.”

Far from brown envelopes and shady meetings where everything is revealed in one fell swoop, leaks to journalists usually start with a morsel, given on purpose or by mistake, which sets reporters on a certain trail.

In over a decade in political journalism, “I’ve only ever been given one proper big leak, which ended up making a splash in the paper I worked for,” the journalist added, “and the person who gave it to me did it for money. That was unusual.”

It’s a rare occurrence because no one person will have access to every possible bit of information on one story; they can share only what they know, then rely on the hack to reach out to people who can help build a fuller picture.

It is also usually the case that political insiders do not want to be wholly responsible for one seismic leak. There is safety in numbers, and being one of several blabbers will always be better than potentially being singled out as the one chatty rat.

A natural follow-up question should be: why do people even leak information when it could cost them their reputation, or even their job? Well, it depends.

As a former government special adviser explained, “There are several ways in which people leak. Sometimes it’s by accident, and they give up information that they don’t realise is important in the course of conversations.”

What is obvious to some will not be obvious to others. It can be hard to know what is an open secret, what is known by all, and what really should stay hidden.

“Sometimes it’s because Westminster is based on the currency of information,” they continued, “and people quite often want to pretend that they’re more important than they are – and their stock-in-trade is information.”

What you know can be just as important as what you do in British politics; marking yourself as someone who is in the thick of it can elevate you in the minds of your peers. Of course, it is a fine line; staffers can further their career by hinting to journalists that they are terribly well informed, but too much gossiping will make them look needy and unreliable.

Being known as a sieve is not something you can usually come back from. The streets of SW1 are littered with the ghosts of advisers who realised this only once it was too late.

Still, it feels worth reiterating that most of what makes it to the papers does so purely because British politics is built on casual conversations. MPs and staffers talk to each other; those staffers talk to journalists, who talk to special advisers, who talk to ministers and to each other, ad nauseam.

Information is constantly floating around and, sometimes, some of it will happen to be in the public interest and make it into print. Once that starts happening, things can get sharper very quickly.

As ‘partygate’ has shown, tattling calls to tattling everywhere; few people want to throw the first stone but once it has happened, heads suddenly start appearing above the parapet.

Thanks to modern technology, it has also become easier than ever to leak information confidentially. When sources once had to meet journalists in person to hand over hastily photocopied documents, now anything and everything can be discreetly pictured and sent on WhatsApp.

This is one of the reasons why it feels like leaking is currently out of control; give people the means, and they will deliver the goods. That is, however, only one part of the equation. If people are happy and secure in their jobs, they are unlikely to try and drown their own government, even if doing so would require minimum effort.

That every day now feels like it comes with its own serving of dramatic leaks means that – at risk of stating the obvious – Number 10 isn’t currently a happy ship. There are few ways in which people can fight back in politics if they feel they have been treated wrongly; handing journalists helpful information is one of the only weapons at their disposal.

In short: if the hull keeps filling up with water, it is probably a sign that whoever is at the helm isn’t doing a very good job.