In this paper we present historical evidence and a theoretical analysis of the
origins of political stability and instability in Colombia for the period 1850-1950,
and their relationship to political, particularly electoral, institutions. We show that
the driving force behind institutional change over this period, specifically the move
to proportional representation (PR), was the desire of the Conservative and Liberal
parties to come up with a way of credibly dividing power to avoid civil war and
conflict, a force intensified by the brutal conflict of the War of a Thousand days
between 1899 and 1902. The problem with majoritarian electoral institutions was
that they did not allocate power in a way which matched the support of the parties
in the population, thus encouraging conflict. The strategic advantage of PR was that
it avoided such under-representation. The parties however could not initially move
to PR because it was not 'fraud proof' so instead, in 1905, adopted the 'incomplete
vote' which simply allocated 2/3 of the legislative seats to the winning party and
1/3 to the loser. This formula brought peace. The switch to PR arose when the
Liberals became condent that they could solve problems of fraud. But it only
happened because they were able to exploit a division within the Conservatives.
The switch also possibly reflected a concern with the rising support for socialism
and the desire to divide power more broadly. Our findings shed new light on the
origins of electoral systems and the nature of political con
ict and its resolution.