Those looking for good news these days can find it in a March 23 Supreme Court decision recognizing that sometimes people really do take actions based on factors other than race.

Even better, the court decision was unanimous. Great racial comity may result.

In Comcast v. National Association of African American-Owned Media, all nine justices agreed that in a tort lawsuit alleging racial discrimination, the plaintiff must prove that the business decision in question was indeed motivated by — get this — actual racial discrimination. Amazingly, common sense prevails.

Of course, for years, at least in contexts other than tort law, the Supreme Court has been narrowly and often bitterly divided about whether mere racial disparities, even without proof of racial intent, serve as grounds enough to penalize a defendant for racial discrimination. Sometimes the court’s race-related reasoning has been so convoluted that it invites more controversy into more cases, rather than giving a clear, easily applied answer. In one example, Grutter v. Bollinger in 2003, Justice Sandra Day O’Connor wrote for a bare 5-4 court majority that, in effect, the exact same legal standards for race-based remedies somehow should be applied differently 25 years hence than it was then.

In short, the court has let confusion reign in numerous areas of racial discrimination law.

That’s why the March 23 Comcast case was a welcome relief. To see all nine justices agree on a bright-line test for what does and doesn’t amount to unlawful discrimination is to believe legal sanity can return. (Justice Ruth Bader Ginsburg did write separately to take exception on one procedural front but otherwise joined the unanimous result.)

What’s especially encouraging is that the justices got it right.

The case originally was filed by Byron Allen, a black entrepreneur who owns the Entertainment Studios Network. ESN wanted Comcast to carry its various channels, which include Comedy.TV and Pets.TV. But, as the court explained, “Comcast refused, citing lack of demand for ESN’s programming, bandwidth constraints, and its preference for news and sports programming that ESN didn’t offer. ... ESN didn’t dispute that, during negotiations, Comcast had offered legitimate business reasons for refusing to carry its channels.”

In sum, the market supported other channels more than it supported ESN. Nonetheless, ESN sued, alleging that Comcast’s refusal to carry its channels unfairly disfavored African American-owned media companies.

A district court sided with Comcast, but the Ninth Circuit Court of Appeals reversed the decision in favor of ESN. The Supreme Court, though, said the district court, not the Ninth Circuit, was correct and ruled in favor of Comcast.

The court’s reasoning was simple and clear. It said that for a plaintiff to win a tort due to racial discrimination, it must show it probably would have received the contract or benefit, or not suffered the alleged injury, “but for” (meaning “except for”) the defendant’s allegedly unlawful conduct. In other words, if the race of the plaintiff caused the decision adverse to him, he may have a case. Contrarily, if legitimate, nonracial factors impelled the decision, the suit isn’t viable.

A decision or action adverse to a black plaintiff isn’t racially discriminatory merely because he is black. It is illegally discriminatory if it was based on his blackness. In this case, if a white plaintiff owned channels with the same profile as ESN’s channels, Comcast almost certainly would have declined to include them in Comcast’s lineup, just as it refused ESN. The plaintiff must show the decision was racial, not purely business.

All nine justices agree that statutes and precedents compel this decision. So does moral wisdom. One good way to tamp down racial resentments is to stop assessing every dispute through the prism of race.