brass neck

From stick one's neck out.

• "This year's commemorations of the start of World War One are a stark reminder of the sacrifices politicians make with other people's lives – except nowadays they'll do so wearing a Help for Heroes t-shirt (almost entirely covering their brass necks). When it comes to the hypocritical lauding of the armed forces while simultaneously shafting them, no one does it better than this government."
• "That’s why it’s particularly outrageous for the government to sneak out its rubbish “blueprint” for cycling and walking on Easter Sunday, and having the brass neck to try to spin its laughably small investment in cycling and walking as a genuine attempt to make them people’s choice for shorter journeys and to reduce the rate of cyclists killed or seriously injured."
• "Theresa May’s former chief of staff has accused the UK’s chief Brexit negotiator, David Frost, of having a “brass neck” after he said the UK government had “blinked first” in negotiations."
• "After the Conservatives’ economic failure left working people worse off, it takes some real brass neck for the Tory top team to tell the public that it’s really all their fault. It’s the same old Tories. They haven’t changed and they’ve learned nothing."
• "And it will need a strong hand to wield that knife, and it will need a steady nerve besides, because they have necks of brass, these aristocrats, I tell you: brass necks, all of them!"
• "Mostly, though, open data acts as a deterrent against committing fraud in the first place, since it would take the brassiest of brass necks to post a fake dataset on a public website."

• brass-balled
• brass-necked
• brass-neck
• [to have] a neck like a jockey's bollocks