According to The Economist, the latest US federal budget includes incentives for “congestion pricing” of roads.

Ostensibly, this is about reducing congestion. But some municipalities like the idea of charging for roads because it represents a new revenue stream. This creates an incentive to charge a price above cost. When a firm does this, we call it a “monopoly price.”

But when a government monopoly forces you to pay a fee to use a good or service, do not call it a price. It is a fee that a government collects by fiat. In other words, it is a tax.

A price is a voluntary exchange of money for a good or service. The emphasis on voluntary is important, because it is this aspect of the price that enables economic calculation for what people really want. Even a free market “monopolist” (however unlikely or conceptually vague it may be) engages in voluntary exchange.

On the other hand, a bureaucrat “playing market” by imposing fees on government-controlled goods and services will not have the same results as a market process. For starters, unlike a person making decisions on their own behalf, a government bureaucrat has to guess at costs. Under a voluntary system, a cost is the highest valued good or service you voluntarily give up in order to attain a goal. But the bureaucrat is dealing with other people’s money.

To “objectively” determine costs, in order to set “fair” prices, is a chimera. In the words of Ludwig von Mises, “[a] government can no more determine prices than a goose can lay hen’s eggs.”