Justice Stevens measures an opinion's relevance by its social significance

In a recent interview with Justice Stevens, the senior Justice has this to say about a recent decision (in which he was in dissent) that upheld a federal ban on partial birth abortions:

On the issue of abortion, however, Stevens has failed to persuade Kennedy to vote consistently with the liberals. I asked Stevens about the decision last term in which Kennedy, writing for the five more conservative justices, upheld the federal ban on partial-birth abortion. Stevens said that the federal ban was deeply flawed and that Kennedy’s rhetoric about the need to protect women from the emotional trauma of abortions was frustrating. But he noted that the real-world effect of the defeat was minimal because of the widespread availability of alternative abortion procedures. “The statute is a silly statute,” he said. “It’s a silly statute.” He added, “It’s just a distressing exhibition by Congress, but what we decided isn’t all that important.”

I couldn't help but be alarmed by that last bit. If the Court gets something wrong, it's very important. The social effects are ancillary to proper interpretation of the Constitution. Ironically, this quote comes just after he gets finished talking about how he is shocked that people consider him to be liberal.