Candidates for the Conservative Party leadership – a job that currently comes with the side gig of prime minister of the United Kingdom – are already seeing their professional records trawled. However, their private lives and characters have also become a point of extreme scrutiny. This is a human story about certain people putting themselves forward for an extraordinary job that few of us would ever care to undertake.

In my recent research with members of the UK parliament, I found that it is certain people with very particular psychological characteristics that climb furthest up the greasy pole of politics.

Politicians who had reached the top of their profession to hold frontbench jobs like secretary of state, minister or even prime minister tended to be those who scored highly for self-enhancement values. This means they are more ambitious than their backbench colleagues and tend to place more importance on leadership, success and social recognition.

In fact, MPs scoring highest for one self-enhancement factor in particular – achievement values – were almost 30 times more likely to have held a frontbench position than those scoring lowest for this value factor. Achievement values relate strongly to a need for self- and social-esteem. People high in these values seek to display their competence and impress those around them. That's true both in their personal and occupational lives.

Frontbenchers also scored much lower than their backbench colleagues for conservation values. These manifest in submissive self-restriction, a desire to maintain stability and the preservation of traditional cultural ideas and customs.

People who place little or low importance on conservation values tend to be more socially disruptive and more likely to violate social expectations. They are less concerned about upsetting others with their actions. In fact, MPs in the sample scoring lowest on one conservation factor, conformity values, were 66 times more likely to have served on the frontbench during their career than those scoring highest on this value factor.

However, MPs who are attracted to new, stimulating and challenging experiences were less likely to stay in elected politics compared to MPs who scored lower on this value factor. For these MPs, who may love the fight and adrenaline of the campaign trail, the burden of constituency work and long debates in parliament about, for example, the correct height of post boxes may understandably lack the sustained excitement they crave.

And MPs who value safety and stability in their own lives and society (and so score highly on security values) also stayed in office almost ten years less than colleagues with the lowest scores for this value factor. Politics is an unpredictable game and this clearly impacts on the type of people who "stick the course".

Measuring values

These findings are based on analyses of survey data collected from 106 national politicians in the UK. I examined the impact of basic human values (as one measure of personality) on the professional success of participants in their political careers – how many votes they won in elections, how long they stayed in office, and how "high" they climbed in the parliamentary hierarchy.

Basic values serve as cognitive criteria for how we judge ourselves and others. Our specific mix of values will often depend on experiences that are peculiar to our social backgrounds, parental guidance, gender, childhood traumas or ethnicity. Values often remain stable after childhood and they can predict our ideologies, attitudes and behaviours in most daily activities.

In this study, I found that basic values make very little impact on how many votes an MP will win in an election but they do have a significant effect on how long they stay in parliament once elected and whether they make it to the frontbench to hold a ministerial post. These results support similar research in Belgium.

The Tory leadership

Holding frontbench political office in a democracy necessarily demands a certain set of skills and characteristics. These are associated with confronting others, arguing for and defending beliefs, and leading others. At the same time, they are associated with manipulating or persuading people to behave for you in certain ways. It may well be that MPs high in self-enhancement values and low in conservation values are much more suited to these roles than their peers – however much a cynical public might dislike the idea.

These characteristics are also self-evident in a number of the candidates currently auditioning for prime minister. As Sonia Purnell writes in the precis to her biography of Boris Johnson: he is "a hugely ambitious figure with seemingly no huge ambitions to pursue – other than, perhaps, power itself".

These findings raise some worrying questions about who seeks high office and how they lead the country when they get there. Voters may want MPs who are honest, philanthropic or authentic, but these might not be the characteristics that get you ahead in parliament.

Frontbench MPs – regardless of party affiliation – seem more motivated by personal success and less likely to inhibit their own emotions or intentions in order to please, placate or compromise with others. Indeed, Esther McVey and Dominic Raab, who unlike Johnson have promised no-nonsense politics and a commitment to a no-deal Brexit, are stunning examples of this characterisation. When the country and the Conservative Party itself remains deeply divided on the issue, and parliament has already rejected no deal, McVey and Raab continue to take tough stances even if they alienate many colleagues and potential voters in the process.

Meanwhile, Rory Stewart – a former diplomat who wants to seek consensus on Brexit through citizens' assemblies – appears far more amenable to seeking compromise. This may be exactly why he doesn't win.

Whoever does emerge victorious will enter the office of prime minister to the same political crisis that Theresa May left behind. How they deal with these challenges may come down to their own personalities as much as anything else.

James Weinberg, Research Associate in Political Psychology and Citizenship Education, University of Sheffield. This article is republished from The Conversation under a Creative Commons license. Read the original article.