WHAT’S THE STORY?

AS Labour and the Tories suffer defections to The Independent Group, it’s worth looking back to the last time there was an attempt to form a new centre force in British politics, which is presumably what Chuka Umunna, Luciana Berger, Anna Soubry and their eight – at the time of writing – colleagues in the group intend to do.

There are parallels between the current split in the ranks of the Labour and Conservative parties and the establishment of the Social Democratic Party (SDP) in 1981. With all due respect to the new Independent Group, apart from Umunna and Soubry, none of them have the profile of the Gang of Four, whose breakaway from the Labour Party led to the formation of the SDP.

READ MORE: Seven Labour MPs resign from party to start new 'Independent' group

WHO WERE THE FOUR?

THEY were all big hitters for Labour. Roy Jenkins was the former home secretary and chancellor of the exchequer during Harold Wilson’s premiership who had also been deputy leader of the party and the UK’s only president of the European Commission – a distinction which he will now always hold. David Owen had been foreign secretary under PM Jim Callaghan from 1977 to 1979 and was widely tipped as a future Labour leader. Shirley Williams was the education secretary who brought in comprehensive schools but lost her seat in the 1979 General Election. Bill Rogers had been transport secretary under Callaghan and was known for his centrist views.

All four of them had become disenchanted in private and public with Labour’s leftward drift after the 1979 election, won by Margaret Thatcher’s Tories. Labour’s one-day conference early in 1981 was the last straw for them as it brought in a new voting system for the election of the party leader that showed the growing power within Labour of trade union leaders and left-wing groups such as Militant. That conference also committed Labour to withdrawing from the common market and to a policy of unilateral nuclear disarmament. With Michael Foot already proving a divisive and ineffective leader, the Gang of Four decided to leave – the party drifting left, a leader not up to the job, divisions over Europe ... does that sound familiar?

On January 25, 1981, the four confirmed they were leaving Labour and forming the Council for Social Democracy. Their first statement was made at Owen’s home in London, hence its name the Limehouse Declaration.

WHAT DID THEY DO NEXT?

ON February 5, 1981, a full-page advertisement in The Guardian announced that the Council had received 8000 messages of support, including 100 by people who were named – the 100 included four former Labour ministers. The council quickly changed to becoming the Social Democratic Party and

within weeks no fewer than 28 Labour MPs had defected to the SDP, but only one Tory, Christopher Brocklebank-Fowler MP. The defecting MPs were from all parts of the UK, with Dr J Dickson Mabon (Greenock and Port Glasgow) and Robert Maclennan (Caithness and Sutherland) the two MPs for Scottish seats.

The National:

Shirley Williams duly joined them in the Commons when she famously won the Crosby by-election in November, 1981, the party’s first election victory. The Gang of Four had by then met Liberal Party leader David Steel and the two centrist parties formed an alliance which basically said they would not stand against each other and would campaign together.

READ MORE: Labour split sees calls for Scottish independence grow

WHAT HAPPENED IN SCOTLAND?

THE new party received a huge boost when the redoubtable Bunty Urquhart, Labour’s former assistant Scottish organiser, came out of retirement to become the SDP’s organiser in Scotland. All her formidable skills were put to the service of Roy Jenkins when he came to fight the Hillhead by-election in March, 1982. It had been caused by the death of the long-serving Tory MP for Hillhead, Tam Galbraith, and with Jenkins at his imperious best, the SDP won the seat with 33.4% of the votes. The SDP was now on the scene electorally and in alliance with the Liberals they were out-polling Labour and the Tories. It really looked as if this third force with avowedly centrist policies might win power. Then on April 2, 1982, the Argentine forces invaded the Falklands…

DID THE SDP SPLIT THE CENTRE-LEFT AND HELP THATCHER STAY IN POWER?

NOT really. The truth is that after the Falklands, she steamrollered all opposition in the 1980s. The Liberal-SDP Alliance also had their internal disagreements, especially after Owen became leader, and by the time the two parties formally merged to become the LibDems in 1988-9, the Gang of Four was no more with Owen forming the continuing SDP that only lasted to 1990.

There is still an SDP. Based in Scotland, led by William Clouston, it has one elected member, Patrick O’Flynn, the MEP who defected from Ukip three months ago.