Government intervention to correct market failure (taxation, subsidies, price controls, regulation and public provision) and government failure.

What this dot point is asking

WJEC wants you to explain the main tools governments use to correct market failure (taxation, subsidies, price controls, regulation and public provision) and to analyse government failure, where intervention worsens the allocation of resources.

The answer

Tools of intervention

An indirect tax equal to the external cost shifts marginal private cost up to marginal social cost, internalising a negative externality and moving output to the social optimum while raising revenue. A subsidy to a good with positive externalities lowers its cost and price, raising consumption towards the optimum. Price controls set legal limits: a maximum price below equilibrium (a price ceiling, for example rent control) protects consumers but creates excess demand and shortages; a minimum price above equilibrium (a price floor, for example minimum alcohol pricing or farm support) supports producers or curbs harmful consumption but creates excess supply. Regulation uses rules, standards, licences and bans (emissions limits, age restrictions). Public provision has the state supply pure public goods and merit goods such as defence, the NHS and state education, funded by taxation.

Why each tool can correct failure

The art of policy is matching the tool to the failure. A negative externality is well suited to a tax that internalises the cost; a public good must be provided collectively because no price can be charged; a merit good can be subsidised, provided directly, or promoted through regulation and information. Real policy usually combines tools: tobacco is taxed, regulated (advertising bans, age limits) and addressed through public information, because no single instrument fully corrects the failure.

Government failure

Government failure has several causes. Imperfect information means governments cannot know the exact external cost, so taxes and subsidies are set at the wrong level. Unintended consequences arise, such as black markets and shortages from a maximum price, or surpluses and waste from a minimum price. Administrative and enforcement costs can be large and may outweigh the welfare gain. Intervention can distort incentives, for example a subsidy keeping inefficient firms alive. And decisions can be shaped by political self-interest (short-term, vote-driven choices) and regulatory capture (regulators acting in the interest of the firms they regulate). These mean intervention is not automatically beneficial and must be judged case by case.

Examples in context

Example 1. Minimum alcohol pricing in Wales and Scotland. Wales (following Scotland) introduced a minimum unit price for alcohol to cut the over-consumption of a demerit good with negative externalities (health costs, crime). As a price floor it raises the price of the cheapest, strongest drinks, targeting harmful consumption while leaving moderate drinkers little affected. It illustrates a price control used to correct market failure, and the debate over its effectiveness and regressiveness illustrates the risk of government failure.

Example 2. Sugar and tobacco taxes. The UK Soft Drinks Industry Levy (the "sugar tax") and high tobacco duties internalise the external health costs of demerit goods and raise revenue. The sugar levy notably changed firm behaviour, prompting reformulation to lower sugar content. Yet such taxes are criticised as regressive (a larger burden on lower incomes) and for being hard to set at the level that exactly corrects the externality, showing both the corrective potential of taxation and the practical limits that can lead to government failure.

Try this

Q1. State two tools a government can use to correct market failure. [2 marks]

• Cue. Any two of: indirect taxation, subsidies, price controls (maximum or minimum prices), regulation, public provision.

Q2. Explain one cause of government failure. [3 marks]

• Cue. For example imperfect information meaning a tax or subsidy is set at the wrong level, unintended consequences such as black markets from a price control, or regulatory capture; explain how it leads to a worse allocation of resources.