HENRY DEEDES sees Jacob Rees-Mogg waxing lyrical about constitutional affairs 

Ask a politician about their favourite subject and you’ll be lucky to be home before the sparrows start chirping.

With Gordon Brown it was economics. Aides could be detained for hours while the former prime minister riffed on the soggier points of fiscal theory.

Pity the poor journalist tasked with calling eurosceptic drag Sir William Cash for his views on the latest happenings in Brussels. 

Pub bores on their fifth pint deliver more succinct arguments. Discussions with Jacob Rees-Mogg (Con, NE Somerset) on the British constitution are similarly best avoided, as MPs yesterday discovered.

The Leader of the House was taking business questions when Pete Wishart (SNP, Perth and N Perthshire) decided, not unusually, to goad him over his recent appearance on Newsnight.

Discussions with Jacob Rees-Mogg, pictured, (Con, NE Somerset) on the British constitution are similarly best avoided, as MPs yesterday discovered

This time, it was over his announcement that any change of prime minister would almost certainly result in a general election, as the UK is now effectively a ‘presidential system’. 

Mr Wishart hailed this as evidence that the magisterial Rees-Mogg had turned republican. 

‘Perhaps somebody should notify the Queen,’ he chuckled. ‘Last week, he was flattering the precious Union, this week he is reinventing the republic of the UK!’

Naturally, Wishart thought he was being frightfully clever. Again, nothing new there.

Each week he treats us to a weekly cabaret, the chamber reverberating with the sound of his own laughter.

The mere mention of constitutional matters prompted Jacob’s ears to prickle. He unfurled his legs, rose to the dispatch box and purposefully corrected his spectacles. 

In Mogg-land, these carefully choreographed shimmies are the equivalent of the first shake of the matador’s muleta.

Turned out Jacob had been fulminating over this issue for some time. Ever since the second reading of the Fixed-term Parliaments Act 2011 on September 13, 2010, in fact, when he had spoken on the matter.

The date of that debate, by the way, tripped off his tongue like a boyish history pupil recalling the signing of Magna Carta.

At Casa Mogg, one would not be surprised if copies of his Parliamentary speeches are framed and hung in the downstairs lav.

The Leader of the House was taking questions when Pete Wishart, pictured, (SNP, Perth and N Perthshire) decided, not unusually, to goad him over his recent appearance on Newsnight

For the next few minutes, Jacob delivered a miniature masterclass on how our Parliamentary system has evolved down the years, discombobulating members with his meandering, discursive prose.

It was like being gently slapped across the cheeks with a copy of Erskine May. Wishart folded his arms exasperatedly as if to say, ‘Gawd, wish I’d never even raised the subject.’

Rees-Mogg’s mouth moved with such a pace, it was a struggle to keep up with what he was saying. Something about the PM’s powers being ‘de facto if not de jure’.

His colleagues too seemed to be struggling. Around the House, eyeballs bobbled. Wishart suddenly let out a long exasperated laugh before eventually, Rees-Mogg resumed his seat. ‘More!’ came the cry from the Tory backbenches.

Hansard’s stenographers will record Rees-Mogg’s ad-libbed oration went on for several minutes. Not once did he hesitate, deviate or repeat himself. The luvvies on Just a Minute would have swooned.

It was a quiet and uneventful day in the Commons otherwise.

An afternoon debate to mark Holocaust Memorial Day meant members were expected not to table any urgent questions.

Publicity-prone Tobias Ellwood (Con, Bournemouth E) hadn’t got the memo. Earlier he’d informed Sky News he had asked for an urgent question on the Afghanistan evacuation. The Speaker wasn’t happy.

Naughty Tobias. Perhaps he should turn down TV interviews for a week as penance if he could possibly manage it.

The only other thing to report was a rare sighting of former attorney general Geoffrey Cox (Con, Torridge and the Cayman Islands) who took time out from billing clients to attend environment questions.

Been a while since we’ve seen Coxy’s magnificent form sprawled across the backbenches. Too busy with those tax returns, perhaps. He was not called to speak, however.

It’s possible Sir Lindsay reserves preference for MPS who bother to turn up on occasion.

As for Sue Gray’s report into Partygate, there was still no sign of it. At this rate it’ll be time to put the tinsel up again before the thing lands.