The courts' doctrine on administrative severability clauses, however, does not share Chevron/Skidmore's incentive structure. Promulgating a severability clause through notice-and-comment procedures can be costly. It may entail significant ex ante costs associated with investigating and reflecting on the various regimes that might result from an enforceable severability clause. Furthermore, the agency may believe that a severability clause entails higher expected ex post costs. For example, an agency may be concerned that a severability clause will make weaknesses in its regulatory program easier to detect. Or an agency may think that a severability clause will weaken its position in litigation,+ either because a court may wonder why the agency included a severability clause if the agency believed that the regulatory program was lawful (142) or because the court may feel it easier to partially invalidate a rule that contains a severability clause. (143)
Under current judicial doctrine, the agency receives little payoff for incurring these ex ante and ex post costs. As explained in the previous section, courts tend not to give substantial deference to severability clauses, preferring instead to conduct the same severability analysis that they would perform in the absence of a severability clause. This lack of deference may often be the decisive factor for an agency considering whether to include a severability clause in a rule. For example, the National Indian Gaming Commission responded to a comment requesting that it include a severability clause in one of its rules as follows:
The Commission ... addressed [the suggestion that the Commission include a severability clause in its rule] in the previous preamble, stating that severability clauses are not conclusive of an agency's intent and that "the ultimate determination of severability will rarely turn on the presence or absence of such a clause." (144) Thus, an agency considering whether to include a severability clause in a rule may conclude that the potential benefits are not worth the candle. The absence of a deference framework specifically for administrative severability clauses is a critical feature of a vicious cycle in which courts do not defer to severability clauses, so agencies do not include them, so courts have no occasion to reconsider whether they should defer to them.
Our aim here is not to suggest that agencies should include a severability clause in every rule. Even if rulemaking were costless, including a severability clause in a rule would not be advisable under some circumstances. First, severability is not advisable when the rule's efficacy depends on the interconnectedness of its provisions. (145) Second, a severability clause might prove to be misguided if the agency does not know whether it would want a court to sever a challenged provision. (146) Third, there may be some provisions that are severable and others that are not, and it may be difficult to predict which combinations should result in severability. Finally, although a regulatory remainder left standing may be preferable to the court's invalidation of the entire rule, the benefits of that regulatory remainder will not always outweigh the drafting costs of promulgating a severability clause.
Our point here is that the current doctrine on administrative severability clauses does not give agencies adequate incentives to include these clauses in their rules even though these clauses can often benefit regulatory schemes more than agency positions on severability developed in litigation. As we have explained, even if courts adopt our proposal by developing a deference framework for administrative severability clauses, an agency will sometimes have good reasons for not including a severability clause in a rule. However, a framework for severability clauses would ensure that agencies will be compensated for their upfront investment in drafting severability clauses and would thereby expand an agency's options for creating the best regulatory scheme with its scarce resources.
DEFERENCE TO ADMINISTRATIVE SEVERABILITY CLAUSES
This Part proposes a deference framework for severability clauses. Before introducing that framework, we first debunk the primary argument against judicial deference to administrative severability clauses--namely, that severability clauses are not the best evidence of the agency's intent regarding severability. We then explain the framework that courts should follow when reviewing an administrative severability clause.
Disassociating Statutory and Administrative Severability Clauses
Part I demonstrated that regulatory schemes containing severability clauses would benefit in several important ways if courts deferred to an agency's opinion on the intent and workability questions expressed in a severability clause. Part II, however, showed that courts tend not to defer to severability clauses. Rather, courts typically give a rhetorical nod to the existence of a severability clause but then conduct their own de novo review of agency intent and workability. This doctrinal treatment of administrative severability clauses is symptomatic of the federal courts' tendency to treat severability analysis in administrative law as substantially the same as severability analysis for statutes. The key, then, to understanding why courts hardly defer to administrative severability clauses is to understand their treatment of statutory severability clauses.
Severability clauses ordinarily state in plain terms that Congress intends for a court to sever an unconstitutional provision from a statute's remainder. Federal courts typically regard clear statutory text as strong evidence of Congress's intent. (147) Why then do courts look past the plain text of a severability clause to analyze severability de novo? The accepted explanation is that statutory severability clauses are boilerplate provisions. (148) We have not seen this argument systematically developed, but it might proceed in the following way: severability clauses are not reliable evidence of Congress's intent because they are generally added to statutes without much (or any) consideration by members of Congress or their staffs. Therefore, a reviewing court is justified in looking past a severability clause because Congress was likely much more concerned with the statute's substantive provisions than with the severability clause.
We hear the ring of truth in the claim that Congress is institutionally ill-equipped to have an informed view of the workability of severability clauses. In particular, several features of the legislative process in Congress (which we describe below) justify a court's scrutiny of a statutory severability clause's apparent meaning. If the rulemaking process within the administrative agencies shared these features, then the parallel treatment of statutory and administrative severability clauses might be justified. However, in several important ways, the rulemaking process is substantially different from the process of drafting statutes. Indeed, the reasons for thinking that Congress lacks capacity and incentive to consider the severability of statutes are, interestingly, reasons to think that agencies have such capacity and incentive. We consider three such reasons below.
l. Attention Paid to Severability Clauses
Some commentators have argued that members of Congress and their staff do not pay much attention to severability clauses. Instead, legislative counsel throw them "unthinkingly ... into a statute without considering whether [they] really want each provision of [their] handiwork to stand independently." (149) Because Congress uses severability clauses so "indiscriminately," a reviewing court could reasonably conclude that, if taken literally, severability clauses would "cover situations which they were never intended to reach." (150)
The process by which administrative agencies decide to include severability clauses in rules, however, is vastly different from this supposed congressional process. Agencies do not just throw severability clauses into their regulations. As we explained in Part II.B, even the most active user of severability clauses--the FTC--has included a severability clause in only 6.3% of its rules from 2000 to 2014. (151) Moreover, unlike Congress, agencies may not include severability clauses in their rules unthinkingly because the APA's rulemaking procedures require agencies to respond to public input about their rules. To be sure, congressional committees do hold regular hearings on proposed legislation that would in theory permit the public to provide input about severability clauses. Administrative agencies, however, are required to respond in a rational way to public comments; otherwise, their rules can be set aside as arbitrary and capricious. (152) Moreover, our research suggests that agencies tend to respond with care to comments suggesting the inclusion or removal of severability clauses. For example, in response to one set of comments, the Fish and Wildlife Service explained: "We recognize that severability clauses are frequently used in legislation but have decided that such a clause would not be useful in the current rule." (153) Similarly, in the statement of basis and purpose for one of its rules, the National Indian Gaming Commission wrote:
[S]ome commenters advocated for the inclusion of a severability clause .... [T]he Commission declines to include a severability clause in this regulation because it believes that the regulations are not so intertwined that striking one provision would necessarily always require invalidation of the entire part, and the lack of a severability clause will not compel a court's finding on the issue. (154) In short, there is no evidence that administrative agencies throw severability clauses unreflectively into their rules.
Even if members of Congress and their staffs were inclined to reflect on...