A-Level Economics May/June 2025 Q3(b): Assess whether an increase in the tax on a demerit good is always the best way to reduc…

1 answer

• ▲0
  accepted ✓

  A demerit good is a product that is over-consumed in a free market, primarily due to information failure and the presence of negative externalities in consumption. The social costs of its consumption exceed the private costs. Governments often intervene to reduce the consumption of such goods, like cigarettes or high-sugar drinks, to a more socially optimal level. An indirect tax is a common policy tool, but whether it is always the best way is debatable.

  An increase in an indirect tax, such as an excise duty, is designed to internalise the negative externality. By imposing a tax on producers, their costs of production rise, causing the supply curve to shift vertically upwards (or leftwards) from S1 to S2 (S1+tax). This leads to a new equilibrium at a higher price (P2) and a lower quantity demanded (Q2). The reduction in quantity from Q1 to Q2 achieves the primary goal of reducing consumption. A key advantage of this method is the 'double dividend': not only is consumption reduced, but the government also gains tax revenue. This revenue can be hypothecated to fund services that mitigate the harm of the demerit good, such as using revenue from a sugar tax to fund school sports, or it can be used for general government spending.

  However, the effectiveness of a tax is critically dependent on the price elasticity of demand (PED) for the product. Many demerit goods, particularly those that are addictive like tobacco, have highly price-inelastic demand. In this case, a significant increase in price resulting from the tax will lead to a proportionally smaller decrease in the quantity demanded. While the policy will be successful in raising substantial tax revenue, it may be relatively ineffective at achieving its main objective of significantly reducing consumption. Furthermore, such taxes can be regressive, as they take a larger percentage of income from low-income households, who may be more likely to consume the demerit good, thereby worsening income inequality. A very high tax rate could also incentivise the creation of a black market, where the product is sold illegally without tax, undermining the policy's objectives and creating further social problems.

  Alternative policies may be more effective, depending on the specific nature of the demerit good. For instance, government regulation in the form of a complete ban or age restrictions can be highly effective at directly controlling quantity. The UK's ban on tobacco advertising and smoking in public places has significantly contributed to changing social norms and reducing smoking rates. Another alternative is information provision. Public health campaigns or mandatory graphic warnings on cigarette packaging aim to correct the information failure that leads to over-consumption. This empowers consumers to make more informed choices and can shift the demand curve itself to the left, which can be more effective long-term than simply moving along it. For tackling issues like binge drinking of cheap, high-strength alcohol, a policy of minimum unit pricing, as implemented in Scotland, may be more targeted and effective than a general tax which affects all products.

  In conclusion, an increase in tax is a potent but imperfect tool and is certainly not always the best way to reduce consumption of a demerit good. Its effectiveness is limited by the price inelasticity of demand characteristic of many such goods, and it carries the risk of being regressive and fostering black markets. While it serves as an excellent revenue generator, its primary goal of reducing consumption may be better achieved, or at least strongly complemented, by other policies. The 'best' approach is rarely a single policy but rather a combination of measures. For example, a tax can be implemented alongside a powerful public information campaign. The tax reduces affordability while the campaign tackles the underlying information failure, creating a synergistic effect that is more powerful than either policy in isolation. Therefore, the optimal strategy is context-dependent, tailored to the specific good and the societal goal, and almost always involves a multi-pronged approach.

  ---

  How it reaches the top band

  • Knowledge / Analysis / Evaluation — The essay demonstrates detailed knowledge by accurately defining demerit goods and explaining the mechanism of an indirect tax using supply and demand analysis (described in words). The analysis is developed by critically examining the role of Price Elasticity of Demand (PED) in determining the tax's effectiveness, a key analytical point. Evaluation is woven throughout the response and is the central focus. The essay directly addresses the 'assess' and 'always the best' aspects of the question by weighing the pros and cons of the tax (e.g., revenue generation vs. regressive impact) and then systematically comparing it with a range of alternative policies (regulation, information provision, minimum pricing). The conclusion provides a sophisticated and justified judgement, rejecting the idea that tax is 'always' best and arguing persuasively for a context-specific, multi-policy approach, thereby reaching the highest level of evaluation.

  Common ways to drop marks

  • Merely describing how an indirect tax reduces quantity without assessing its limitations, such as the impact of PED.
  • Failing to discuss any alternative policies, which makes it impossible to 'assess' if tax is the 'best' way.
  • Treating all demerit goods as the same, without acknowledging that the 'best' policy might differ for cigarettes versus sugary drinks.
  • Writing a conclusion that simply repeats earlier points without offering a clear, supported judgement on the question asked.

  Examiner tip: Always deconstruct the question to identify evaluative trigger words like 'assess', 'best', or 'always', and ensure your argument directly engages with these terms from the introduction to the conclusion.

  ---

  AI-generated exemplar, grounded in the official Cambridge assessment bands and reviewed by the MarkScheme team. Mark your own answer →

  @markscheme_answers

Your answer

Sign in to answer this question.