Roadworks and discommoded rodents might be to blame for the current outbreak of twitching nostrils in the Dáil.

Micheál Martin is sniffing the atmosphere like an undernourished bloodhound. Gerry Adams has the purposeful air of a man just returned from the local hardware store with a consignment of traps in his pocket.

Perched high and hawkish in the top back corner, Mick Wallace and Clare Daly remain alert to the slightest movement in the political undergrowth.

And Enda. Well Enda, being Taoiseach, has been supplied with a special peg by the permanent Civil Service and has been wearing it on his nose with great effect for the last while. He can’t smell a thing. It’s the rats, you see.

We blame the Luas works currently under way in the vicinity of Leinster House, forcing neighbouring varmints to seek alternative accommodation in the already crowded corridors of power.

It’s proving a move too far for many of them. They succumb quickly to the tedium and drop dead under the floorboards .

At the height of the stink last week, the Ceann Comhairle was out of the country. When he came back to the chamber on Tuesday, it nearly knocked him out.

But, thanks to a very large dose of unpalatable humble pie, Seán Barrett muddled through. But he’s not himself. He’s been very quiet ever since.

This presents a further problem in the critter department. When the Ceann Comhairle becomes agitated – and he’s a martyr to the agitation – his voice rises several octaves until only dogs and rats can hear him. The two-legged ones can take refuge in their offices; the four-legged variety run away.

Important notice: we have consulted our legal people. We have been exchanging letters. Pursuant to our discussions and the standing orders, Dáil Sketch wishes to make it absolutely clear that we are not comparing any members of Dáil Éireann to the rodent or canine population. (What they might say to each other, about each other, in the privacy of the members’ bar is their own business.)

Much obliged, yer honour. Where were we? In the Dáil, with the nostril-twitchers.

When the Ceann Comhairle was away – he took himself off to Prague on Government business – it seems the rats came out to play and duly expired from boredom.

Mick Wallace was first to smell a rat in the chamber. He asked the Taoiseach if the debate on the establishment of a commission of inquiry into the findings of the Guerin report on alleged Garda misconduct in the Border region was pulled because, among other reasons, former minister AlanShatter had written letters to him. Enda made no audible reply. But Wallace insists he answered in the negative by shaking his head.

The next day, Martin and Adams loudly signalled that they could smell a rat now too. They were gagging across the floor at this stage.

Adjusting his peg ever so slightly, Enda explained that the Ceann Comhairle had made an independent ruling and that was his business. As for letters from former minister Shatter, some had indeed been sent to his department.

But what matter? Never mind the letters, his Government is going ahead with the commission, without any change to the terms of reference.

This wasn’t good enough for Martin and Adams, who stormed on to the plinth to get some fresh air and media coverage.

After a weekend of Opposition complaints about the dead rat smell, and an overwrought intervention over the phone to a radio programme from the Ceann Comhairle, matters came to a head on Tuesday.

Barrett accepted his decision to shut down the debate might have been a bit hasty. But we all make mistakes.

And proactive Enda, with an alacrity which pointed to no desire on his part to cut Shatter any slack, published all the correspondence between them. To put it in legal terminology, his Government told Alan to sling his hook, they’re going ahead with the inquiry anyway.

And there it seemed to end.

But Gerry Adams couldn’t let go yesterday. He could still smell that rat.

He felt the Taoiseach hadn’t been forthright enough when first asked if letters were received from Shatter. The Sinn Féin leader declared it was clear that Enda “engaged in a series of evasions and diversions to avoid giving a full, accurate and timely account to the Dáil” of the ongoing correspondence with Shatter.

The Government backbenchers threw their eyes to heaven, given that nothing changed as a result of the former minister’s letters. They muttered about pots calling kettles black.

As for that smell, Fianna Fáil was already divining it elsewhere. This time in relation to the rules governing what can be said at the banking inquiry. As Barry Cowen put it: “It is absolutely farcical to have a banking inquiry where people cannot name a bank.”

Could this be true?

Again, the Taoiseach insisted these were not his rules, but were as a result of all-party agreement.

And then, as the afternoon wore on, a new theory emerged on the Dáil’s dead rat epidemic. Rodents are not in the frame anymore for the pong in the chamber.

It came courtesy of a strange tweet from Adams.

“Flatulence is a curse.”

No wonder nostrils were twitching.