Politics is a trade. Voters might like to think they want to elect people who come from all walks of life. But when it comes down to it they mostly cast their ballots for candidates who are already politicians.

An analysis by The Herald shows that 37 of Scotland’s 59 MPs had done paid political work before they first entered the House of Commons.

That does not mean they do not have previous real world experience – many do. But it does suggest they are also schooled in machine politics, in constituency working, in public engagement ... and in spin.

The 37 MPs identified as professional politicians were councillors or the staffers for parties or politicians – or often both. In many cases this gave them real insight into the constituencies where they stand or the job they are about to do.

Others were in related backgrounds – a trade union organiser or third-sector professionals.

Scotland’s latest crop of MPs also include those drawn from traditional gateway professions for politics, such as law and journalism.

More than one in 10 MPs are lawyers. There are four journalists, three accountants, two former police officers, a doctor, an actor, a musician, an engineer, a farmer and several people who have run their own businesses.

Only one MP, Falkirk barber John McNally, has a traditional blue-collar trade.