In the 1990 film Air America, Mel Gibson’s character Gene Ryack describes what he calls “the politics of Saturday night.” He once judged countries by a wonderfully simple standard: how good was Saturday night for the ordinary person living there?

It’s a humorous line, but behind it is a serious principle: outcome-based evaluation.

Political arguments are often framed around intentions. A program is intended to help the poor. A regulation is intended to protect workers. A tax is intended to make society fairer. A tax cut is intended to encourage investment. A subsidy is intended to make something affordable.

Those intentions may be admirable. But intentions aren’t outcomes.

The more useful question is: What actually happened?

Did people become more prosperous? Did their real purchasing power increase? Did housing become more affordable? Did wages keep pace with prices? Did people become safer? Did they gain opportunities and choices? Did they have more control over their own lives?

In other words, when Saturday night arrives, after the rent or mortgage, groceries, utilities, taxes, insurance, transportation and everything else have been paid, what is left?

Not merely money, either. Saturday night represents disposable income, certainly, but also leisure, security and personal freedom—the ability to spend your time and money according to your own priorities.

That makes the politics of Saturday night enticing. Politicians naturally want to promise us a better Saturday night: lower taxes, higher benefits, cheaper services, more generous subsidies or some combination of them.

But there is an important addition to Ryack’s philosophy:

Everything has a price.

Government benefits must ultimately be financed. Tax reductions have consequences for revenue unless accompanied by spending reductions or offsetting economic effects. Subsidies shift costs rather than making them disappear. Regulations can produce benefits while also imposing costs. Borrowing can move today’s costs into the future.

A government can therefore manufacture a very enjoyable Saturday night by putting the bill on the national credit card.

That doesn’t necessarily mean the expenditure was unwise. Some things are worth paying for. Public infrastructure, national defense, education, social insurance and countless other activities can produce benefits that justify their costs.

But the cost still exists.

That is why genuine outcome-based evaluation has to look beyond both intentions and immediate benefits. It asks what a policy produced, what it cost, who received the benefits, who bore the costs, and whether the arrangement can be sustained.

The real test of the politics of Saturday night, then, isn’t simply whether the party is good.

It’s whether we can afford the bill when Sunday morning comes.

The Politics of Saturday Night: Who Pays for the Sunday Morning Hangover?