When Maureen Colquhoun became Britain's first openly lesbian MP in 1974 her party turned on her, and so did the electorate. Paul Linford reports

Anyone looking for a measure of how far British society has changed over the past 35 years need look no further than the career of the former Labour MP Maureen Colquhoun.

At the time of her election to the Commons as MP for Northampton North in 1974, she appeared to be a happily married woman with three grown up children.

In fact she was to leave her husband shortly afterwards to set up home with a female partner, magazine publisher Barbara Todd, thereby becoming Britain's first openly lesbian MP.

Nowadays, no-one would bat an eyelid. But back then, in an era when the Labour Party was if anything more puritanical than the Tories, it sparked a chain of events which eventually led to the loss of her seat.

The attitude of the then Commons Speaker, former Labour cabinet minister George Thomas, was perhaps typical of those that prevailed in the party at the time.

When Ms Colquhoun asked him, in February 1976, to refer to her in the chamber as Ms rather than Mrs, he seemed rather bemused and thought she was asking to be referred to as Miss.

This semi-public acknowledgement of her estrangement from her husband was also the signal for the press to declare open season on Ms Colquhoun, with Daily Mail gossip columnist Nigel Dempster gate-crashing her and Ms Todd's housewarming party.

Today's Labour Party would doubtless have leapt to her defence, but not then. As her local party chairman Norman Ashby sensitively put it: "She was elected as a working wife and mother... this business has blackened her image irredeemably."

Indeed it had, at least in their eyes, and in September 1977 members voted by 23 votes to 18 to deselect her, citing her "obsession with trivialities such as women's rights".

Ms Colquhoun was not without her supporters, however, and following an appeal to the party's National Executive Committee, which found she had clearly been removed on the grounds of her sexuality, she was reinstated as Labour's candidate.

But the damage had been done, and at the 1979 general election she was decisively beaten by the Conservative challenger.

This was Tony Marlow who, as a rebellious Eurosceptic, himself went on to become one of the more unconventional figures on the right during the Thatcher-Major years.

It was perhaps understandable that Ms Colquhoun never attempted to return to Westminster as an MP, but she did go back there as a parliamentary assistant to various other Labour members during the early 1980s.

She served on Hackney Borough Council from 1982-1990 and, after moving to the Lake District, on the National Park authority there between 1998 and 2006.

During that time she campaigned for speed limits on Lake Windermere and argued that members of the park authority should disclose their membership of the Freemasons.

She was most recently in the news for attacking as "political correctness" a decision to axe guided walks on the fells on the grounds that they only attracted "white, middle-class, middle-aged people".

Paul Linford is a political blogger and former parliamentary lobby journalist. He is editor of www.holdthefrontpage.co.uk