Power-sharing ‘discontinuities’: Legitimacy, rivalry, and credibility

Abstract

Power-sharing arrangements between a leader and a popular outsider can be mutually beneficial and threatening. The literature has focused primarily on the former’s trade-off where a leader gains legitimacy when sharing power with a respected outsider but also subsequently creates a rival who could challenge their rule. Yet this outsider also faces a simultaneous trade-off between power and credibility in acquiescing to the leadership. I incorporate both coinciding trade-offs in developing a formal model to examine such power-sharing arrangements which have been prevalent historically and currently. I illustrate a ‘discontinuity’ in optimal power sharing where a leader either shares nothing or shares a specific amount to compensate the rival for the rival’s lost credibility. Counterintuitively, I further show that the leader should share more power with less trustworthy rivals to reduce their strong incentives to challenge. I then revisit the Investiture Controversy in medieval Europe using these insights from the model.

Editors’ Introduction to JTP issue 30.2

“… 1. In particular, see Baron (2018), Pant (2018), Mele and Seigel (2017), Sawaki (2017), and Serra (2018). …”