ANDREW MITCHELL endured weeks of screaming newspaper headlines and opposition barracking. But the government’s chief whip, who was involved in a class-inflected altercation with police officers in September, could not survive the displeasure of the Conservative MPs who were supposed to answer to him. His resignation on October 19th was yet another victory for backbenchers, who have notably failed to toe the party line on the European Union, university tuition fees, House of Lords reform and a variety of other issues. By one measure this parliament is the most rebellious since the second world war (see chart).

The trials of coalition are partly responsible for the surly mood. Conservative and Liberal Democrat backbenchers smart at the compromises made by their leaders: no one was elected on the coalition agreement, they argue. Lib Dems and Tories tend to rebel on different issues, bumping up the overall rate. But Philip Cowley, an expert on parliamentary rebellions at the University of Nottingham, believes the fundamental shift towards rebellious behaviour is unlikely to be reversed. MPs’ relations with their constituency parties, voters and the media have changed, in a way that encourages them to become more obdurate. The big shift is that MPs have become more rooted in their constituencies. Many new Conservative MPs were selected—often for their worldly, independent-minded credentials—early in the last parliament and spent years nursing their constituencies before the 2010 election. Small wonder they are now so willing to challenge party policy. In the wake of the 2009 MPs expenses scandal an anti-politics mood prevails. In the public imagination, “MP” evokes a venal, faceless technocrat. A typical comment in one of a series of focus groups recently organised by Policy Exchange, a think-tank, was: “a lot of them start off fine, then they just toe the party line because they’ve got to”. In this cynical environment, idiosyncratic politicians are more likely to thrive, as Boris Johnson, the rarely on-message Tory mayor of London, has shown. More MPs are becoming electoral entrepreneurs, striking out on their own. A distinct personal profile is particularly valuable when support for a party is falling. At the 2010 election, the decline in the Labour vote was smaller, by just over two percentage points, in seats where a party incumbent was standing for re-election. A Conservative backbencher points admiringly to Gisela Stuart, a Labour MP who at the last election held a seat in Birmingham that “should be Tory”, thanks to her independent reputation and strong local campaign. Ms Stuart has long been one of the most outspoken Labour MPs.

Technological change has reinforced this trend towards dissent. In the past ornery MPs had fewer opportunities to vent, and party enforcers could crack down on those who voiced unorthodox thoughts in broadcast or print interviews. That has changed. In today’s cacophony of Twitter messages, it is easier for MPs to express their views unchecked. As Alastair Campbell, Tony Blair’s former spin doctor, recently noted, “command-and-control communications” of the kind that was once his hallmark simply “wouldn’t work as well”.

The internet has also increased the pressure on MPs from their constituents. Through social networks and vote-tracking websites, voters, constituency parties and local news outlets can spot what their representatives are up to and harangue them. One ringleader of last year’s huge Conservative rebellion over a referendum on EU membership says that it was “incredibly easy” to persuade MPs to join because they were already under intense pressure from their constituency associations. Gone are the days when an MP could vote with the government, then sign a contradictory early-day motion or two to muddy the waters, he adds. These days it is “harder to bluff”.

The changing shape of political careers has encouraged dissent, too, says Tim Bale, a political scientist. Many MPs are drawn from the ranks of special advisers, whose former proximity to those at the top of the party makes them less deferential, and from professions that over the past decades have become less hierarchical and more meritocratic. Once elected, they have a relatively small period in which to rise through the ranks—the parties like their leaders young and sprightly. Many miss it, and become serial rebels.

And they find alternatives to the ministerial ladder. The internet, 24-hour news and new media make it easier for MPs to achieve recognition as experts on particular policy areas. Parliamentary select committees are more prominent and powerful than ever before. A new MP expresses bafflement at colleagues who have given up the independence and influence of select-committee membership to become supine parliamentary private secretaries (the lowly first rung on the ministerial ladder).

In some ways this signals a return to the distant past. Douglas Carswell, an MP and author of a new book on technology and democracy, notes that before universal suffrage an MP enjoyed a personal relationship with the small number of residents eligible to vote in his constituency. Mass politics and mass media broke this link. But technological and cultural shifts are “repersonalising” politics, says Mr Carswell, and creating a “long tail” of distinctive parliamentary identities. Mr Mitchell’s successor as chief whip, Sir George Young, had better be ready for that.