Political parties formed by existing MPs are significantly more likely to die

Political parties formed in Europe by existing parliamentarians are significantly more likely to die, new research shows.

The conditions of the births of parties have an impact on their life, death and any mergers with other parties, experts have found.

Parties formed by MPs are more likely to die in their midlife, those with connections to social organizations are more likely to die either early or late in their life.

The research, by Nicole Bolleyer, Patricia Correa, and Gabriel Katz is published in the Journal of Politics. Experts used data about the evolution of 204 political parties in 22 democracies, including their births and deaths, between 1968 and 2016.

A party formed by existing parliamentarians—with "insider status" is more likely to be dissolved—with the risk increasing by an average of 1.93 percentage points. They were 3.15 percentage points more likely to dissolve a decade after their foundation.

Dr. Katz said, "By then, the MPs who helped build the new formation may have deserted it or their political careers may have ended. The departure of these founders—interested in protecting their own position of power—tends to disrupt insider parties, as they are unlikely to have invested in procedures for leadership renewal earlier on. Insider status has no significant impact on the probability of merging in early stages."

"15 years after their birth, the likelihood of merging becomes almost 2 percentage points higher for organizations with insider status than for those without it. This difference remains significant for about 17 years and becomes statistically indistinguishable from zero afterward: by then, the leadership of an insider party will have been fully socialized into and recruited from the party organization and, thus, may be more inclined to protect its separate identity."

Parties born with the support of pre-existing societal organizations—"social rootedness," are on average 2.13 percentage points less likely to dissolve.

Neither insider status nor societal rootedness have an influence on the probability of political parties merging.

Political parties with a new ideology are less likely to merge with others—there was an 0.83 percentage point decline in the likelihood of merging over the average sample party's life span.

The average probability of merging for parties that were built from scratch is statistically indistinguishable from zero, regardless of whether they are ideologically novel.

A party formed with the support of a pre-existing societal organization is 1.77 percentage points less likely to dissolve than a formation without a societal base in the first 18 years of its existence.

Professor Bolleyer said, "These resources can be critical in limiting the risk of dissolution—especially during adolescence, when the organization is not yet institutionalized and is therefore particularly vulnerable. As parties mature organizationally and broaden their support base, promoter organizations matter less. The probability of dissolution between parties with and without external societal support becomes statistically indistinguishable over the next decade of their lives."

Parties formed by existing parliamentarians are more likely to die in their midlife. Those with connections with societal organizations are less likely to dissolve early or late in the life of the political party.