Where Your Tax Dollars Go: Public Goods and Services

Learning Objectives

• Distinguish between a public good and a private good.
• List common categories of government spending funded by taxes.
• Explain why some goods are hard to fund without collective payment.

Core Content

Economists use the term 'public good' for something that is both non-excludable (you can't easily stop people who didn't pay from using it) and non-rivalrous (one person using it doesn't use it up for others). Streetlights are a classic example — once they're installed, it's hard to stop a non-payer from benefiting, and one person walking under the light doesn't dim it for the next person.

Because public goods are hard to sell profitably one customer at a time, private businesses often won't build them. That's the gap taxation fills. Common categories funded by tax revenue include infrastructure (roads, bridges, water systems), public safety (police, fire, courts), education (public schools), defense, and social programs (healthcare support, unemployment assistance, retirement systems).

Not everything government spends money on is a pure public good — some spending is on services that could theoretically be sold privately but that a society has decided to fund collectively for other reasons, like ensuring broad access regardless of income. Public education is a good example: private schools exist, but most countries also fund public education because broad literacy and basic skills benefit the whole society, not just the individual student.

Understanding this distinction helps you evaluate tax policy debates later — arguments about taxes are often really arguments about which goods should be public, which should be private, and how much collective funding is enough.

Worked Example

Question: If a private company built a toll road and only people who pay a toll can drive on it, is that road a pure public good?

Student: It doesn't sound like it, since you can be excluded if you don't pay.

Guide: Right — that's the excludability test. What does that tell you about who tends to build toll roads versus free public roads?

Student: A private company can profit from a toll road because they can charge each user. A free public road can't charge each user, so it makes more sense to fund it through shared taxes.

Guide: That's the core logic. Excludability is often what determines whether something gets built privately or funded publicly.

Practice Quiz

Question 1. A public good is best described as one that is:

A) Expensive and rare B) Non-excludable and non-rivalrous C) Only used by wealthy people D) Always free to build

Question 2. Which of the following is the best example of a public good?

A) A private car B) A streetlight C) A restaurant meal D) A personal phone

Question 3. Why do private businesses often avoid building pure public goods?

A) It's illegal B) They can't easily charge each user, making it hard to profit C) Governments ban private infrastructure D) Public goods are never useful

Question 4. A toll road that excludes non-payers is:

A) A pure public good B) An example of an excludable service, unlike a free public road C) Illegal in most countries D) The same as a public school

Question 5. Public education is funded collectively partly because:

A) Private schools are illegal B) Broad literacy benefits society beyond just the individual student C) It costs nothing to run D) Only wealthy families need it

Answer Key

1. B, 2. B, 3. B, 4. B, 5. B

Answers and Explanations

1. Non-excludability and non-rivalry are the two defining features economists use for public goods.

2. A streetlight is hard to restrict to paying users and doesn't run out from more people using it.

3. If you can't charge users individually, it's difficult to build a profitable private business around the good.

4. Because toll roads can exclude non-payers, they can be built and run privately in a way a free public road cannot.

5. Collective funding for education reflects a societal decision that broad access produces benefits beyond the individual.

Key Takeaways

• Public goods are non-excludable and non-rivalrous, which makes them hard to fund through private sale alone.
• Tax revenue commonly funds infrastructure, public safety, education, defense, and social programs.
• Excludability is often the deciding factor in whether something gets built privately or collectively.
• Some collectively funded services aren't pure public goods but are funded broadly for access and societal-benefit reasons.
• Debates about taxes are often really debates about which goods should be public versus private.