The Volokh Conspiracy

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Slippery Slope Arguments

Judicial-Judicial Equality Slippery Slopes and the Extension of Precedent


[a] Simply Following Precedent: A Legal Effect Slippery Slope.—One of the most common "A will lead to B" arguments is the argument that judicial decision A would "set a precedent" for decision B. This generally means that (1) A would rest on some justification J and (2) justification J would also justify B.

{Sometimes this sort of argument is made not to illustrate the practical risk that A may lead to B, but to use situation B as an illustration that the underlying theory of rule R is unsound. My discussion here, though, focuses primarily on the practical argument.}

Consider, for instance, the debate about whether the government should be allowed to ban racial, sexual, and religious epithets (beyond those that fit within the existing fighting words and threat exceptions). To uphold such a ban (decision A), the courts would have to give some general justification for why these words should be punishable, essentially creating a new exception to First Amendment protection.

If this justification J were that "epithets add little to rational political discourse and are thus 'low-value speech,' which may be punished," then courts could likewise use this J to uphold bans on flag burning, profanity, and sexually themed (but not obscene) speech, all examples of speech that some argue is of "low value" (result B). In fact, a lower court might feel bound to reach result B because of precedent A's acceptance of justification J. We might call this process a legal effect slippery slope, because B follows from A as an application of an existing legal rule (the obligation to follow precedent).

A related legal effect slippery slope may happen when the justification underlying A is vague enough that it could justify B, even if this effect isn't certain. Thus, suppose the Supreme Court concludes that campus bans on racial, sexual, and religious slurs are constitutional (decision A) because under a totality-of-the-circumstances balancing test the benefits of allowing the bans outweigh the costs (justification K). Proponents of the decision may claim that K wouldn't justify bans on reasoned arguments about biological differences between the sexes, about the supposed immorality of various religious belief systems, or about the supposed failings of various race-based cultures (result B). But it's hard to confidently accept this assurance—K is vague enough that future judges could equally well conclude that K does justify or even require B.

Likewise, a decision and its underlying justification may sometimes grant extra authority to some decisionmakers. Imagine a proposal to ban all racist advocacy, and not just slurs, justified by the theory that racist ideas are wrong and therefore aren't constitutionally protected.  A court that accepted this justification would also be setting a precedent that courts have the authority to decide which ideas are wrong and therefore punishable. Once this added authority is accepted, other bad decisions might follow from it: for instance, other judges might use this authority to uphold the suppression of antigovernment ideas, antiwar ideas, or socialist ideas.

So far, the way that A can lead to B is clear: if A sets a precedent that embodies justification J, then lower courts in future cases may feel legally bound to apply J as well. Coordinate courts and the same court would also feel that they ought to apply J, unless there is a strong reason to reject the precedent.

But this legal effect slippery slope doesn't by itself provide much of an argument against result A, because advocates of A could simply urge courts to implement A based on a narrower justification that avoids the excessive breadth or the added authority that would lead to B. For instance, A's advocates could argue that bans on racial, sexual, and religious slurs are constitutional because

  • only racially, sexually, and religiously bigoted epithets are "low-value speech" and can thus be prohibited (J1);
  • epithets are "low-value speech" and thus may be restricted if a sufficient level of harm is shown—and this level of harm is present for racially, sexually, or religiously bigoted epithets but not for other epithets (J2);
  • epithets are "low-value speech," but the Court has the authority to draw such a conclusion only about epithets, not about more reasoned discourse (J3).

Under each of these justifications, A's defenders would argue, bad result B would not necessarily follow as a direct legal effect. Arguing that judicial decision A will lead to B thus requires more than just an assertion that "A will set a precedent for B." Defenders of A can always craft some legal justification for A that distinguishes it from the unwanted result B.

[b] Extension of Precedent as a Judicial-Judicial Equality/Administration Cost Slippery Slope.—But that a distinction between A and B can be drawn doesn't mean that enough future judges will be persuaded by this distinction. Even judges who aren't legally obligated to follow precedent A, because its justification is not literally applicable to current case B, might still feel impelled to extend A beyond its original boundaries.

Consider, for example, justification J1, which would authorize A (racial epithets are punishable but others are protected) but not B (epithets, bigoted or not, are unprotected). Supporters of J1 believe that racial epithets and other epithets are distinguishable, but some Justices might not be persuaded by the distinction. They may particularly oppose restrictions that they see as viewpoint-based. They may oppose giving flag burning, which they see as an anti-American epithet, more protection than other epithets get. Or they might simply conclude that bigoted epithets are not materially different from other epithets, and believe that their duty to treat like cases alike obligates them to treat all epithets the same way. Those Justices might therefore view A as the least satisfactory position, less appealing than either 0 or B.

Say, then, that the Justices form the following blocs (bloc I and bloc II can have any number of Justices between 1 and 4, so long as they add up to 5):

Group Most prefers Next preference Most dislikes 0→A A→B 0→B Attitude Voting strength
I 0 B A + "More speech
protection is
best, but distinguishing
bigoted epithets from others is the
II A 0 B + "More speech
protection is
best, but distinguishing
bigoted epithets from others is the
III B A 0 + + + "Restrict epithets as much as possible" 4

On a Court where the Justices fall into these blocs, a proposal to move directly from "epithets protected" (0) to "all epithets unprotected" (B) would lose 5-4; only bloc III would prefer B over 0. But a proposal to move from 0 to "bigoted epithets unprotected" (A) would win, with the support of blocs II and III. A proposal to move from A to B would then also win, with the support of blocs I and III. And any proposal to then move from B back to 0 would lose, so long as even one Justice is willing to adhere to precedent even though he substantively prefers 0 to B.

So in our scenario, the bloc II Justices believe that bigoted epithets should be treated differently from other epithets, and their arguments may be logically defensible. But in practice, the arguments were not fully persuasive to blocs I and III, and so the bloc II Justices got what they saw as the worst result—their desire to create an exception for bigoted epithets led to the denial of protection to all epithets. Thus, even with no changes to the Court's personnel, a decision A that doesn't legally command B (and that some Justices see as consistent with the rejection of B) might still bring about B through the equality slippery slope.

Equality slippery slopes may be particularly likely in judicial decisionmaking. Judges are expected to explicitly justify their decisions, and to have principled reasons for the distinctions they draw. They may therefore be more reluctant than legislators or voters to adopt what they see as logically unsound compromises, which is how the judges in bloc I would view result A.

{Equality slippery slopes may be especially likely in areas such as First Amendment law, where equality along some axis (for example, with respect to the viewpoint of the speech) is a strong constitutional norm. Thus, though some Justices (bloc II) may believe that racist epithets are different from other epithets, those that don't accept this position may feel an especially great compulsion—stronger than they would in doctrinal areas where equality is a weaker requirement—to treat the two kinds of epithets similarly.}

This sort of slippery slope may have occurred during the evolution of free speech law in the mid-1900s. Consider decision A, the rule that the government may not restrict political advocacy unless the advocacy creates a "clear and present danger" of some serious harm; decision B, the extension of this protection to entertainment as well as serious political discourse, a step the Court took in the 1948 Winters v. New York decision; and decision C, the extension of this protection to sexually themed speech, at least so long as the speech falls outside the narrow obscenity and child pornography exceptions.

The six-Justice majority in Winters relied in large part on the difficulty of administering any dividing line between political advocacy and entertainment. Likewise, the Court eventually concluded that sexually themed entertainment should be protected alongside other entertainment, largely because of a need to treat ideas—whether about sex or about politics—equally. The clear-and-present-danger cases did not precedentially require the Winters result, and Winters, in turn, did not require the protection of sexually themed speech. But the precedents, combined with the Justices' concerns about administrability and equality, led to the law we have now, through precedential evolution rather than precedential command.

Some of the Justices who adopted the clear-and-present-danger test in the 1930s and early 1940s might have wanted B and C as well as A. But some might have been surprised by the eventual slippage, and might have thought twice about supporting A—at least in its pure form, with no qualifying language—had they anticipated these results. In 1942, for instance, the Court still assumed that "lewd," "profane," and "obscene" speech was unprotected, and obscenity was at the time defined to include much sexually themed material that is protected today. As late as 1951, Justice Douglas, who eventually became a solid vote for protecting sexually themed speech, said that "obscenity and immorality" were "beyond the pale."

The slippage from A to B and C was not just the effect, identified by Frederick Schauer, of "linguistic imprecision" or "limited comprehension." Some of the Justices who voted for decisions B and C might have agreed that they were going beyond the boundaries that those who rendered decision A would have preferred. But the Justices would still have been willing to go beyond those boundaries, because they preferred B to A, and C to B.

Thus, a judge deciding whether to adopt proposed principle A may rightly worry that future judges, who have different understandings of equality or administrability than the original judge does, might deliberately broaden A to B. And there is little that the original judge can do when adopting A to reliably prevent this broadening; for instance, saying "But this decision should not lead to B" in the opinion justifying A may have only a limited effect on future decisions, since judges who prefer B to A on equality or administrability grounds may not be swayed much by such a statement.