Unit 10 Women’s right to vote and the reduction in child mortality in the United States

10.8 Scope for political rent-seeking under different political systems

Why do political elites in autocratic systems oppose democracy? And why might they sometimes concede to a more democratic system?

In this section we extend our model of a government maximizing political rents beyond the case of a dictator with absolute power, to other self-interested regimes. We continue to assume that the government is interested only in maximizing total rent. But if its power is limited by the political environment, the constraints that it faces will differ.

Figure 10.14 lists examples of the duration in office of governing elites in a variety of political environments. Elections play a part in the political systems in all of these countries, but in some cases do little to constrain the elite. The longest rule by an individual at the head of a governing elite was by Fidel Castro (49 years) in Cuba, who was then succeeded by his brother Raúl. Although elections are held, Cuba remains a one-party state. There are examples of elected governments removed from power by non-electoral means, and of revolutionary governments—like the Sandinistas in Nicaragua—that are followed by transition to free and fair elections. In India and Mexico, elected political parties maintained a grip on power for decades.

Governing elite Country Rule Came to power by Left power by
Congress Party India 1947–1977 Election (end of colonial rule) Election
Communist Party Cuba 1959– Revolution Still in power as of 2025
Social Democratic Party Sweden 1932– 1976 Election Election
Second Republic Spain 1931– 1939 Election Military coup civil war
Francisco Franco Spain 1939– 1975 Military coup, civil war Natural death; return to democracy
Institutional Revolutionary Party Mexico 1929– 2000 Election Election
Democratic Party US 1933– 1953 Election Election
Sandinista Party Nicaragua 1979– 1990 Revolution Election
African National Congress South Africa 1994– Non-violent revolution and election Still in power as of 2025
Australian Labor Party Australia 1972– 1975 Election Dismissed by (unelected) executive

Figure 10.14 Examples of governing elites, and how they achieved and lost power.

In this section we will think of the government not as a dictatorship that can be removed from power only by revolution, but as a governing elite consisting of top officials and legislative leaders, unified by a common interest such as membership of a particular political party. Now, the government faces opposition within an electoral system, and the governing elite can be removed from office by losing an election.

The duration curve for a government facing elections

We can derive a duration curve in the same way as in the previous section. As before, the government may be removed from office for performance-related reasons—in the model, if it sets too high a level of tax. Or it may be removed for reasons beyond its control—even governing elites that serve the interests of their citizens often lose elections. Again we will assume that the probability of removal for non-tax reasons is 10%. Hence there is a trade-off between the tax level and the expected duration of the government like the one in Figure 10.12: a downward-sloping duration curve. It reaches zero rent at an expected duration of 10 years (which is how long the government would expect to stay in office if every year there was a 10% chance of their being removed).

So what difference do fair elections make to our model? The answer is that the political and electoral system affects how much the government’s expected duration is reduced if it raises taxes above the cost of public services. For example, if citizens can remove the government by voting in free and fair elections we can expect duration to be more sensitive to government performance than in the case of a dictatorship that could only be removed by difficult or dangerous means such as an uprising.

Figure 10.15 shows that the sensitivity of duration to tax rises corresponds to the slope of the duration curve. Suppose that the government increases taxes above the cost of public services by an amount \(\Delta T\) = $25 million. First consider a relatively steep duration curve: the tax rise reduces duration from 10 to 6.4 years, so the change is \(\Delta D\) = 3.57 years. Work through the steps to understand why a flatter curve has greater sensitivity to the tax level, representing a more democratic system. Raising taxes for the purposes of rent-seeking leads to a higher probability of losing elections, and a larger fall of 6.25 years in the expected duration of governance.

Duration curves, democracy, and the sensitivity to tax rises.
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Figure 10.15 Duration curves, democracy, and the sensitivity to tax rises.

A steep duration curve: In this diagram, the horizontal axis shows duration, D, in years, ranging from 0 to 11, and the vertical axis shows taxes, T, in millions of dollars, ranging from 0 to 120. A horizontal line at 5 is labelled cost, C, and corresponds to rent = 0. A single downward-sloping straight line represents a steep duration curve. The slope of this curve is labelled ΔT/ΔD = 7. A vertical dashed line indicates ΔT, extending from T = 5 up to T = 30. A horizontal dashed line indicates ΔD, running from D = 6.43 to D = 10.
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A steep duration curve

If taxes rise above C = $5 million by \(\Delta T\) = $25 million, duration falls by \(\Delta D\) = 3.57 years.
The slope of the duration curve is \(25/3.57 = 7\).

A flatter duration curve: In this diagram, the horizontal axis shows duration, D, in years, ranging from 0 to 11, and the vertical axis shows taxes, T, in millions of dollars, ranging from 0 to 120. A horizontal line at 5 is labelled cost, C, and corresponds to rent = 0. Two downward-sloping straight lines represent duration curves. The upper line is steeper, while the lower line is flatter. The slope of the flatter line is labelled ΔT/ΔD = 4. A vertical dashed line indicates ΔT, extending from T = 30 down to T = 5. A horizontal dashed line indicates ΔD, running from D = 3.75 to D = 10.
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A flatter duration curve

With the flatter curve, the same tax rise of \(\Delta T\) = $25 million causes duration to fall by \(\Delta D = 6.25\) years.
This curve represents a more democratic system. Raising taxes for the purposes of rent-seeking leads to a higher probability of losing elections, and a larger fall in the expected duration of governance.

Duration curves and political systems: In this diagram, the horizontal axis shows duration, D, in years, ranging from 0 to 11, and the vertical axis shows taxes, T, in millions of dollars, ranging from 0 to 120. A horizontal line at 5 is labelled cost, C, and corresponds to rent = 0. Four downward-sloping straight lines represent different political systems. The steepest line, starting at the highest tax level, represents closed autocracy. Below it, a slightly flatter line represents electoral autocracy. Further down, a flatter line represents electoral democracy with some voting limits. The flattest line, starting lowest on the vertical axis, represents electoral democracy with universal suffrage.
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Duration curves and political systems

In more democratic political systems duration is more sensitive to tax levels, so the duration curves are flatter and the feasible set of taxes and duration is smaller. The government is more constrained in its ability to extract rent.

We can think of the differing slopes of the duration curves in the last step of Figure 10.15 as capturing the degrees of political competition in different political systems. The curve is flatter where the political system is more competitive. Just as competition disciplines the owners of firms in the economy by limiting the profits they can get by setting too high a price, competition to win elections is the way that a democracy disciplines its politicians to provide the services desired by the public at a reasonable cost (in terms of taxes).

How political competition affects taxation and rent

The key idea in our model is that political competition makes the likeli­hood of losing an election more dependent on the government’s perform­ance. This means that it makes the duration curve flatter. In other words, an increase in taxes by the government will have a larger effect on the elite’s ex­pected duration in office than it would if there was no political competition.

Then, when the governing elite chooses a tax level to maximize its total political rent, the slope of the duration curve affects how much rent it is able to extract. Figure 10.16 compares the outcome in two situations: where the government faces greater or lesser political competition.

In this diagram, the horizontal axis shows duration, D, in years, ranging from 0 to 11, and the vertical axis shows taxes, T, in millions of dollars, ranging from 0 to 120. A horizontal line at 5 is labelled cost, C, and corresponds to rent = 0. Five downward-sloping convex curves represent isorent lines including rent = 100, 200, and 300. Two straight, downward-sloping duration curves are drawn: the steeper one labelled “less political competition” and the flatter one labelled “more political competition.” Point M lies on the steeper duration curve, tangent to the isorent curve between rent = 200 and rent = 300. Point N lies on the flatter duration curve, tangent to the isorent curve between rent = 100 and rent = 200. These points illustrate the choice of taxes under less and more competitive political conditions.
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Figure 10.16 Choice of taxes under less and more competitive conditions.

In a less-competitive system, the governing elite chooses point M, with high tax revenue of $57.5 million per year, and expected duration of 5 years. With more political competition the feasible set is smaller. The government’s chosen outcome is N, where both annual tax revenue and total rent are lower.

Note that in Figure 10.16, the governing elite in a more competitive political system implements lower taxes but has the same expected duration as the elite in the less-competitive system. This feature of the model arises from the modelling assumptions we have made about the duration curves (they are straight lines meeting the horizontal cost line at the same duration level) and also the government’s objective (to maximize rent). With a more general shape for the duration curve and government indifference curves, more competitive conditions could lead to either longer or shorter expected duration.

This happens because there are two opposing effects of an increase in political competition:

  • Raising taxes brings a heavier risk of the governing elite being dismissed. The duration curve is flatter, so the opportunity cost of an additional year of duration (in terms of lost tax revenue) is lower. This effect on its own would cause the governing elite to choose a higher duration.
  • The governing elite has lost some of its power. The duration curve has moved inward, reducing the feasible set: it has less power to obtain rent because its expected duration is shorter at every tax level. This effect on its own would cause the elite to choose lower duration.

With the particular assumptions in our model these effects exactly offset each other. More competition reduces the tax rate with no change in expected duration.

Why a dictator might resist democracy

The model helps show why governing elites, and the wealthy and powerful members of society who are allied to these elites, have so often resisted democracy and attempted to limit the political rights of the less well-off. When voting is restricted to the wealthy, the elite faces little political competition, and obtains high total rents (point M in Figure 10.16). But now suppose that everyone has the right to vote and opposition political parties are allowed to challenge the elite. The increase in political competition flattens the duration curve and reduces the feasible set. The best the elite can do is choose point N. Democracy has reduced its scope for collecting political rent.

An ‘ideal’ democracy in the model

In our model, greater democracy corresponds to an increase in political competition, flattening the duration curve and constraining the ability of a self-interested elite to extract political rent. A democratic system that was very effective in preventing rent extraction would be represented by a duration curve that was almost flat. We could think of the limiting case of a completely flat duration curve as representing an ‘ideal’ democracy. In such a system, being in government would hold no attractions for purely self-interested politicians. The electoral system would ensure that political parties with other motives—ideology or benevolence, for example—entered the competition for office, and that parties reflecting the preferences of voters would succeed.

Exercise 10.8 Income and substitution effects

substitution effect
When the price of a good changes, the substitution effect is the change in the consumption of the good that occurs because of the change in the good’s relative price. The price change also has an income effect, because it expands or shrinks the feasible set. See also: income effect.
income effect
The effect that an increase in income has on an individual’s demand for a good (the amount that the person chooses to buy) because it expands the feasible set of purchases. When the price of a good changes, this has an income effect because it expands or shrinks the feasible set, and it also has a substitution effect. See also: substitution effect.

Note: To do this exercise, you will need to be familiar with income effects and substitution effects. To review these concepts, read Section 3.7 of The Economy 2.0: Microeconomics.

Using the concepts of income and substitution effects and how they can be analysed in a diagram with indifference curves and feasible frontiers, redraw Figure 10.16 to show the decomposition of the final choice after increased competition into the income effect (reduction in duration, D) and the substitution effect (increase in D).

Extension 10.8 The income and substitution effects of an increase in political competition

Coming soon.