THERE is an old, sexist joke about women in politics.

It is unusual in that it punctures the pomposity of men rather than makes derogatory comments about any perceived incompetence of women. It runs thus: the male of the household tells his mates how he decides the big issues in the house, where the family stands on nuclear disarmament, global warming and the precise stance on Middle East peace talks. He adds: “My wife makes the small decisions: where we live, where the kids go to school, where we go on holiday, what car we have and how we spend our money.”

It is crude but it speaks to a form of matriarchal society that is recognisable to many Scots. It is hardly scientific evidence but my experience is that Scottish society, particularly at the working-class level, was and is strongly influenced or even organised by women. The “broken pay packet” legend – where the man would return home with his weekly wage untouched – was again used as a joke but it nodded to the reality that there was, should and must be a strong feminine influence on how the lives of the family, indeed community, should be lived.

This almost primitive political power of women has been transformed in the century since suffrage and has reached a rarefied level in Scottish politics. The power of women in this country is now such that the three leading parties have women leaders in Nicola Sturgeon (SNP), Kezia Dugdale (Labour) and Ruth Davidson (Conservative). This is not a blip or even a curiosity but part of a distinctive trend. The previous Conservative leader in Scotland was Annabel Goldie. The previous Labour leader was Johann Lamont. Sturgeon comes from an SNP tradition that has as its most famous standard bearers the groundbreaker Winnie Ewing and the late and inspirational Margo MacDonald.

So are there reasons why women play such a strong role in Scottish politics, certainly at the top? Is our nation at the forefront of a march towards a system that will reflect gender at least 50-50? And as we approach the Holyrood elections what is the outlook for women in the Scottish political system?

There is, apparently, something in the notion that culture plays a part. Dr Meryl Kenny, lecturer in gender and politics at the University of Edinburgh, points out: “You are seeing a lot of women making that transition from the ‘small p’ politics to become involved in family issues, local organisations and then to running for office. Women for Independence has facilitated that.”

This point is reinforced by Ruth Wishart, the journalist who has followed Scottish politics for decades. “Women for Independence allowed women to speak in an atmosphere that was accepting. Many women broke the ice there and became comfortable with speaking out publicly. It was a brilliant forum for developing confidence and a voice.”

Both are dismissive of the theory that women have only recently become interested in politics. “Pollsters may tell you that women are less politically interested than men but that is hogwash,” says Dr Kenny. “If you ask conventional questions about what is politics then women may appear less interested but if you open up politics in regard to the family, to the community, to civil society then women are very, very engaged. They just think of politics in a more expansive way.”

The experience of Wishart bolsters this view. She has written about, participated in and influenced politics for most of her life, initially finding her voice in the often tempestuous world of union affairs of the 1970s onwards.

But why has this raised involvement by women in politics happened specifically in Scotland and specifically now?

“It is a combination of a number of things,” says Dr Kenny. “There is a kind of distinctiveness to Scottish politics, particularly post-devolution where there was this sense of a new politics, one that was different to that of Westminster, one that was more inclusive, more participatory. Women’s representation has been a big part of this because it is a very visible sign of how it can be different from Westminster.”

There was also the various quota systems that sought to address the gender imbalance. “The quotas did make an impact,” says Dr Kenny. ”In the Labour Party, where prominent women have come though, not just as leaders, quota measures played a significant role, either twinning in the first election or subsequently measures on the list.”

Wishart pays tribute to Jack McConnell, then-Labour leader in Scotland, for introducing the twinning measures, basically a system that paired seats by winnability and location, allowing a joint selection panel to select one female and one male candidate.

But while women are prominent in leadership, the number of women MSPs has fallen. Of the 129 MSPs elected to the Scottish Parliament for the first time in 1999, 48 were women (37.2 per cent). Dr Kenny points out that this “gender coup” was all the more dramatic given that Scotland and the rest of the United Kingdom had a relatively poor historical record on women’s representation. Her research provides a startling statistic: on May, 6, 1999, more women were elected to the Scottish Parliament in one day than had been elected to represent Scotland in the House of Commons since 1918, when women were first eligible to stand for political office.

This was significantly helped by Scottish Labour implementing gender quotas, using twinning in constituency seat contests and a placement policy on regional lists. The SNP used informal measures which ensured that female candidates were placed in favourable list positions. These measures had a clear impact on headline figures: women made up 50 per cent of Scottish Labour MSPs and 42.9 per cent of SNP MSPs elected in 1999.

Dr Kenny points out the 2003 elections resulted in a modest increase of the proportion of women in the Scottish Parliament, rising to 51 out of 129 MSPs (39.5 per cent). However, since then the numbers have dropped. The 2007 Scottish Parliament elections resulted in a significant decrease in the number of women MSPs elected, dropping from 51 to 43 (33.3 per cent). The 2011 elections represented a small improvement on 2007 – rising to 45 women MSPs (34.8 per cent) – but these results were set within an overall pattern of decline in the number of female candidates selected.

Dr Kenny thus sounds a note of caution over optimism about the redressing of the gender imbalance.

“We should not get too caught up with what is happening at the top and lose sight of what is happening at other levels,” she says. “The simple truth is that the numbers of women in the Scottish Parliament have dropped over consecutive elections. In part, that is because parties have taken their eyes off the ball and stopped using or enforcing strong quota measures. Some parties use them, some don’t.”

She is cautiously hopeful about next week’s elections. “There are indications that more women may be returned because the SNP, the Labour Party and the Greens are using strong quota measures. So that will have an impact on the numbers. But you also have parties like the Conservatives which refuse to use those measures and have absolutely dismal levels of women candidates. If they do as well as expected in some polls, we might not get the huge gains that we might have had otherwise. We might get close to or over that 40 per cent but we are not getting to 50-50.”

This is a chasm that has to be closed. Dr Kenny says: “The simplest argument is the justice argument. It is simply unfair when women are over 50 per cent of the population that they are under-represented. Beyond that there is the argument that having women in positions throughout all levels of politics makes a difference to women’s participation and engagement.

“The third thing – and this is more controversial – is the idea that women may make a difference to politics in terms of the style of politics, the way of working, the interest in certain policies or issues that may otherwise be neglected. There is evidence that this happens but it is not straightforward.” She adds: “There thus may be unreasonable expectations for women. And do we ask these questions of men? No, we don’t.”

Nor, it must be conceded, do we investigate thoroughly or even scrutinise why the leaders of the main English parties are men.