That Geoffrey Cox chose to stand up at the despatch box of the House of Commons and describe himself as Brexit’s “codpiece” asks significantly more metaphor based questions than it answers. Is he, personally, the codpiece? Is the legal codicil to the Withdrawal Agreement he so urgently seeks the codpiece? What does that make the backstop? Who is protecting what from who? Where does Theresa May tuck in?

But none of them move us any further away from what a codpiece, and therefore Geoffrey Cox, is ultimately for, and that is to cover up b*llocks.

The attorney general was back in Westminster on Thursday morning, direct from Brussels, where leaked reports described his latest round of post-negotiation negotiating as “insane.”

We are now well into the third month of Theresa May dispatching various random people to Brussels to renegotiate the Irish backstop who then come back, yet again, with absolutely nothing. Sometimes, when she is really desperate, she even goes herself.

It was why the Labour MP Helen Goodman asked Mr Cox whether it was still government policy to “reopen the withdrawal agreement”, as Theresa May said it was at the end of January, when they have now been told by the EU, somewhere in the region of 10,000 times, that it isn’t going to happen.

It took the Attorney General all of eighteen seconds, in reply to the very first question he had been asked, to yield his lovingly pre-prepared Carry On Negotiating material.

“It is government policy to achieve the necessary change in the backstop,” he said, not answering the question. “That is Government policy; that is the subject of the discussions that we are having. I would say that it has come to be called “Cox’s codpiece”. What I am concerned to ensure is that what is inside the codpiece is in full working order.”

Never one to be afraid to direct the spotlight of another towards himself, speaker John Bercow immediately intervened to repeat the term, playing, as ever, the role of that tedious friend we each have whose contribution to any joke is to kill it.

But no one remains any the wiser as to quite what the codpiece is. As far as the Eurosceptics are concerned, Mr Cox’s role in proceedings is to go to Brussels and kill off the backstop. A codpiece does no such thing, rather it protects and conceals it.

Mr Cox also does not seem at all clear whether his role is to ensure the codpiece itself is in full working order, or its contents. As far as the EU is concerned, the contents of the codpiece are just fine. That is a matter that is concluded. They will not be seeing the light of day again.

Nevertheless, to borrow a suitably Churchillian phrase, Brexit has been doing the bulldog for some time now, and Mr Cox’s comparatively late foray on to its dismal stage has certainly perked things up. Codpieces come in many forms. Whether he imagines himself a piece of sequinned spandex or the full piece of precious Tudor metal he did not make immediately clear.

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But it is reasonable to have one’s suspicions. These two items share a name but have different purposes. One is protective, the other suggestive, an altogether more palatable version of something quite horrid, and possibly dangerous, lurking beneath.