After the pairing debacle, Julian Smith has put May’s government in an even more compromised position

It was Labour who first suggested that the Commons start its summer break five days earlier than planned. Conservative whips, desperate to head off a vote of confidence in Theresa May as party leader, seized on Labour’s idea with delight. Then Labour pulled the plug, leaving the government red-faced. Amid more damaging headlines for May, the “Tory plan” was abandoned.

If Labour laid a trap, as senior Tories believe, then it was just about within the rules of the Westminster game. But Labour’s wicked whippery was pretty minor when compared with the apparent skulduggery of Julian Smith, the government chief whip.

It has been reported that he told up to five Tory MPs to break the pairing arrangement under which they and an opposition MP agreed to miss Tuesday’s knife-edge vote on remaining in a customs union after Brexit. Only one MP broke their deal; that four Tories defied their own chief whip shows how he crossed a line. Pairing is informal but suits all parties, as MPs will inevitably miss some votes. It helps a government more than an opposition, and is even more vital in a hung parliament.

This might sound like another Westminster bubble story that doesn’t matter in the real world. But this one does. Smith claims his only mistake was to tell Brandon Lewis, the Tory chairman, to take part in two crunch votes (but not others) while paired with Jo Swinson, the Liberal Democrats’ deputy leader, who is on maternity leave. It’s not a good look for the Tories, who are already going down in the opinion polls amid bitter divisions over Europe, and now appear untrustworthy and nasty.

To make matters worse for Smith, he has embroiled May in the scandal. She told MPs on Wednesday: “the breaking of the pair was done in error”, apparently unaware that Smith had told other MPs to do so. Andrea Leadsom, the Commons leader, told the House it was “an administrative error”. If the Commons has been misled, it matters. Many Tory MPs, including ministers, are rightly outraged by Smith’s behaviour. He was the talk of the town at Westminster’s summer parties, and not in a flattering way.

In 36 years as a Westminster journalist, I’ve seen the tricks of the whips’ trade. They used to keep a “black book” of rumours about MPs, listing their affairs, visits to gay clubs and other extracurricular activities, and used to threaten them when a tricky vote loomed. Whips did not even care if the gossip was true. They’ve been known to threaten journalists in similar vein. Less is written down these days, and records are shredded after a while, so they cannot be called as evidence in court. But threats are still made. Then there are the loyalty tests. An old trick is to send an email or note marked “to all Tory MPs” to just one suspected leaker to see if it is passed to the media. Neat.

Smith’s actions this week are beyond the pale. Of course, he was under intense pressure. In response to the pairing debacle, a party spokesman said: “We have apologised for the fact that a pregnancy pairing arrangement was broken in error this week. No other pairs offered on the Trade Bill on Tuesday were broken." If the government had lost the customs vote, the number of Tory MPs demanding a confidence vote in May would probably have passed the 48 needed to trigger one.

Smith is lucky the government did not win by just one vote instead of six. In normal times, he may have fallen on his sword, or been sacked. Of course, these are not ordinary times. We have a zombie government that survives not week-to-week but day-to-day. May has already lost her deputy prime minister, home secretary, defence secretary and international development secretary. In recent weeks, she has lost 11 ministers and parliamentary aides who oppose her Brexit strategy, including her foreign secretary and Brexit secretary. She must have had more mini-reshuffles than hot dinners.

So she can ill afford to lose another minister. May must regret moving Gavin Williamson from chief whip to the the Ministry of Defence; he is out of his depth there. Although Williamson liked to model himself on the ruthlessly ambitious Francis Urquhart in TV’s House of Cards, he was more experienced than Smith and so would probably not have broken apparent pairing deals.

Chief whips do not normally speak in the Commons, but that is a convention, not a rule. Smith, who has given conflicting accounts of what happened, should come clean in a statement to MPs before their summer recess starts on Tuesday. He may hope the row blows over during the break. May should tell Smith “never again”, but can she trust him? There will be many more knife-edge Brexit votes this autumn and winter, and they will decide the country's future.

This week's controversy might have a silver lining. It has persuaded more MPs to support proxy voting for those on parental leave (instead of having to pair) when the Commons debates the issue in September. Proxy voting should be extended to include MPs who are sick or carers, as part of a drive to drag parliament's archaic practices into the 21st century.