2136 HARVARD LAW REVIEW [Vol. 129:2118
clear but rather is ambiguous.
89
But how do courts know when a
statute is clear or ambiguous? In other words, how much clarity is
sufficient to call a statute clear and end the case there without trigger-
ing the ambiguity-dependent canons?
Unfortunately, there is often no good or predictable way for judges
to determine whether statutory text contains “enough” ambiguity to
cross the line beyond which courts may resort to the constitutional
avoidance canon, legislative history, or Chevron deference. In my ex-
perience, judges will often go back and forth arguing over this point.
One judge will say that the statute is clear, and that should be the end
of it. The other judge will respond that the text is ambiguous, mean-
ing that one or another canon of construction should be employed to
decide the case. Neither judge can convince the other.
90
That’s be-
cause there is no right answer.
It turns out that there are at least two separate problems facing
those disagreeing judges.
91
–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
A
NALYSIS
257 (2010); see also Re, supra note 34; Brian G. Slocum, The Importance of Being Am-
biguous: Substantive Canons, Stare Decisis, and the Central Role of Ambiguity Determinations in
the Administrative State, 69 M
D
. L. R
EV
. 791 (2010); Lawrence M. Solan, Pernicious Ambiguity
in Contracts and Statutes, 79 C
HI
.-K
ENT
L. R
EV
. 859 (2004); Note, “How Clear Is Clear” in
Chevron’s Step One?, 118 H
ARV
. L. R
EV
. 1687 (2005); cf. J
OHN
F. M
ANNING
& M
ATTHEW
C.
S
TEPHENSON
, L
EGISLATION
AND
R
EGULATION
171 (2d ed. 2013) (“Another concern here is
just how one defines or determines ‘ambiguity’ in the statute’s semantic meaning.”); Susannah
Landes Foster, Note, When Clarity Means Ambiguity: An Examination of Statutory Interpreta-
tion at the Environmental Protection Agency, 96 G
EO
. L.J. 1347, 1362 (2008) (“A fair question is
how agencies should figure out when Congress has been clear.”).
89
See Solan, supra note 88, at 861 (“Part of the problem is that the law has only two ways to
characterize the clarity of a legal text: It is either plain or it is ambiguous. The determination is
important. Whether the text is a statute, a contract, or an insurance policy, once a court finds the
language to be plain, it will typically refrain from engaging in a variety of contextually-based in-
terpretive practices.”); see also id. at 862.
90
See Farnsworth et al., supra note 88, at 276.
91
Of course, this analysis makes two assumptions.
First, it assumes that judges can agree on the meaning of “clarity” and “ambiguity” in the
first place. But as a number of scholars have pointed out, there are many — and conflicting —
definitions of these two terms. See, e.g., W
ILLIAM
D. P
OPKIN
, A D
ICTIONARY
OF
S
TATUTORY
I
NTERPRETATION
11 (2007) (observing that “‘[a]mbiguity’ is ambiguous,” and then providing
three different definitions); Farnsworth et al., supra note 88, at 258 (distinguishing between exter-
nal and internal judgments about ambiguity); Slocum, supra note 88, at 799–802; Sanford Schane,
Ambiguity and Misunderstanding in the Law, 25 T.
J
EFFERSON
L. R
EV
. 167, 171–72 (2002) (dis-
tinguishing between lexical ambiguity and syntactic ambiguity); see also Solan, supra note 88, at
859 (“The problem, perhaps ironically, is that the concept of ambiguity is itself perniciously am-
biguous.”). To complicate things even further, different definitions of ambiguity can lead to dif-
ferent outcomes. See Farnsworth et al., supra note 88, at 271 (“[D]ifferent ways of asking about
ambiguity produce different conclusions about its existence.”).
Second, it assumes that the line dividing ambiguity from clarity remains the same across
(and within) all doctrines. In other words, this analysis assumes that the level of ambiguity neces-
sary for moving to step two of Chevron is the same level of ambiguity required before a court may
consult legislative history. But who knows whether that’s true? In fact, in some cases, the
Supreme Court has implied a different clarity versus ambiguity threshold for certain doctrines.