Legal Sidebari

High Court Strikes Down Provision of Crime
of Violence Definition as Unconstitutionally
Vague
May 7, 2018
A non-U.S. national (alien) may be subject to removal and face other serious immigration-related
consequences if he has been convicted of an aggravated felony. The Immigration and Nationality Act
(INA) defines an aggravated felony to include a “crime of violence” for which the term of imprisonment
is at least one year, and incorporates the federal crime of violence (COV) definition found in 18 U.S.C. §
16. Recently, the Supreme Court in Sessions v. Dimaya affirmed a decision by the U.S. Court of Appeals
for the Ninth Circuit (Ninth Circuit) holding that the language of the second prong of the COV definition,
which covers any felony offense that involves a “substantial risk” of physical force, is unconstitutionally
vague (the first prong of the COV definition, covering an offense that includes as an element the actual,
attempted, or threatened use of force, remains in effect). The Supreme Court relied on its decision in
Johnson v. United States, which held that a similarly worded component of the federal violent felony
definition found in the Armed Career Criminal Act (ACCA), which was employed for sentencing
enhancement purposes, was void for vagueness under the Due Process Clause. By striking down part of
the COV definition, the Supreme Court’s ruling in Dimaya potentially narrows the scope of criminal
offenses that may subject an alien to removal. Beyond the immigration context, the Supreme Court’s
decision narrows the scope of numerous other statutes that incorporate the federal COV definition when
imposing heightened criminal or civil penalties on those who have committed a “crime of violence.”
Background
An aggravated felony conviction imposes serious immigration consequences. An alien admitted into the
United States who has been convicted of an aggravated felony is subject to removal from the country. An
aggravated felony conviction also may result in an alien being barred from many forms of discretionary
relief, subject to mandatory detention by immigration authorities pending removal proceedings, barred
from readmission into the United States, and precluded from acquiring U.S. citizenship. The INA defines
an “aggravated felony” to encompass many enumerated offenses, including a “crime of violence” for
which the term of imprisonment is at least one year. The statute incorporates the two-pronged COV
definition found in 18 U.S.C. § 16:
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(a) [A]n offense that has as an element the use, attempted use, or threatened use of physical force against
the person or property of another, or
(b) any other offense that is a felony and that, by its nature, involves a substantial risk that physical force
against the person or property of another may be used in the course of committing any offense.
In Dimaya, a lawful permanent resident (Dimaya) challenged his order of removal that was predicated on
a finding that his burglary conviction constituted a crime of violence under the second prong of the COV
definition, 18 U.S.C. § 16(b). In his petition for review to the Ninth Circuit, Dimaya argued that § 16(b) is
unconstitutionally vague because it has no standard to determine whether a criminal offense carries a
“substantial risk” of physical force. This ambiguity, Dimaya contended, deprived him of due process.
In 2015, while Dimaya’s case was pending, the Supreme Court in Johnson v. United States held that a
similarly worded provision of the ACCA, which was employed for the purpose of imposing increased
prison sentences on certain firearm offenders convicted of a “violent felony,” was unconstitutionally
vague. Specifically, the ACCA’s multi-pronged violent felony definition included a provision covering a
felony offense that:
[I]s burglary, arson, or extortion, involves use of explosives, or otherwise involves conduct that presents a
serious potential risk of physical injury to another.
The Supreme Court in Johnson determined that the italicized language of this “residual clause” of the
violent felony definition “leaves grave uncertainty” about how to estimate the risk ordinarily posed by a
crime, and that it also has no practicable way to measure the level of risk required to meet the “serious
potential risk” threshold. The Court thus held that the residual clause “produces more unpredictability and
arbitrariness than the Due Process Clause tolerates.”
The Ninth Circuit granted Dimaya’s petition for review, and held that the second prong of the COV
definition, which rendered Dimaya’s burglary conviction an aggravated felony that made him removable,
was unconstitutionally vague. The circuit court concluded that the Supreme Court’s holding in Johnson
concerning the ACCA’s residual clause “applies with equal force to the similar statutory language and
identical mode of analysis used” by the second prong of the COV definition. Apart from the Ninth
Circuit, the Third, Sixth, Seventh, an d Tenth Circuits had also held that 18 U.S.C. § 16(b)’s COV
definition is unconstitutionally vague; the Fifth Circuit, on the other hand, rejected a vagueness challenge
to 18 U.S.C. § 16(b). Faced with this circuit split, the Supreme Court granted certiorari to the
government’s appeal of Dimaya.
The Supreme Court’s Decision
After holding the case over from the October 2016 term, the Supreme Court issued its decision in April
2018. In a 5-4 ruling, the Supreme Court affirmed the Ninth Circuit’s decision. In an opinion written by
Justice Kagan (joined in part by Justices Ginsburg, Breyer, Sotomayor, and Gorsuch), the Court rejected
the government’s contention that civil immigration laws governing removal should be subject to a “less
exacting” vagueness standard under the Due Process Clause than criminal statutes like the ACCA’s
residual clause. Citing Jordan v. De George, a 1951 case where the Supreme Court applied the vagueness
standard to an immigration statute given the “grave nature of deportation,” Justice Kagan opined that “the
Government cannot take refuge in a more permissive form of the void-for-vagueness doctrine than the
one Johnson employed.”
Citing Johnson as “a straightforward decision, with equally straightforward application here,” Justice
Kagan wrote that 18 U.S.C. § 16(b) suffers from the same “constitutionally problematic” features that
infected the ACCA’s residual clause. Justice Kagan’s opinion characterized 18 U.S.C. § 16(b) as
involving an “excessively speculative” analysis to determine a crime’s inherent risk. In particular, the
COV definition’s residual clause covers an offense that “by its nature” involves a substantial risk of
physical force, inviting judges to consider a range of factors such as statistics, surveys, experts, Google,

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and even “[g]ut instinct.” The Court determined that § 16(b) possesses similar uncertainty over how to
assess what constitutes a “substantial risk” of physical force necessary to meet the COV definition. Given
these concerns, the Court concluded that 18 U.S.C. § 16(b) is unconstitutionally vague.
The Court also rejected the government’s claim that 18 U.S.C. § 16(b) involves a “significantly more
focused inquiry” than the ACCA’s residual clause that had been struck down in Johnson. The government
argued that, unlike the ACCA’s residual clause, 18 U.S.C. § 16(b) only requires consideration of the risk
of physical force during a crime’s commission, rather than the risk of potential injury arising after the
crime, and it is not linked to a “confusing list” of enumerated crimes. The Court determined that, although
18 U.S.C. § 16(b) temporally limits its analysis to the risk of force arising “in the course of committing
any offense,” this language made no meaningful difference because analyzing a crime’s inherent risk is
already limited to what usually happens during its commission. The Court also considered the fact that the
COV definition’s second prong focuses on the risk of “physical force” rather than “physical injury,” but
found no significant distinction because both standards require a court to hypothetically envision a
crime’s potential consequences. Finally, the Court noted, although 18 U.S.C. § 16(b) is not preceded by a
list of enumerated crimes like the ACCA’s residual clause, the absence of such a list is immaterial
because the indeterminate features of 18 U.S.C. § 16(b) remain present.
In an opinion concurring in part and concurring in the judgment, Justice Gorsuch agreed that, because 18
U.S.C. § 16(b) “uses almost exactly the same language as the [ACCA’s] residual clause in Johnson,
respect for precedent alone would seem to suggest that both clauses should suffer the same judgment.”
Justice Gorsuch opined, however, that the vagueness doctrine should extend to all civil statutes—not just
the civil immigration law at issue in the case—because many civil laws impose “similarly severe
sanctions” as those imposed by the INA. Notably, Justice Gorsuch identified the vagueness doctrine to be
rooted not only in the Due Process Clause, but also in separation of powers concerns. (Justice Kagan’s
opinion, while describing the vagueness doctrine as a “corollary of the separation of powers,” focused its
vagueness analysis primarily upon the due process implications for an affected individual.)
In a dissenting opinion, Chief Justice Roberts (joined by Justices Kennedy, Thomas, and Alito) argued
that 18 U.S.C. § 16(b) “does not present the same ambiguities” as the ACCA’s residual clause given the
“significant textual distinctions” between those provisions. Chief Justice Roberts argued that, unlike the
ACCA’s residual clause, 18 U.S.C. § 16(b)’s “more constrained” focus on a crime’s inherent risk of
physical force involves “a commonsense inquiry that does not compel a court to venture beyond the
offense elements to consider contingent and remote possibilities.” He further distinguished 18 U.S.C. §
16(b) on the basis that “it is not tied to a disjointed list of paradigm offenses” that each have their own
“varying amounts and kinds of risk.”
In a separate dissenting opinion, Justice Thomas (joined in part by Justices Kennedy and Alito)
questioned whether the vagueness doctrine was rooted in the original meaning of the Due Process Clause,
and whether laws governing the removal of aliens should even be subject to a vagueness prohibition.
Justice Thomas argued, in the alternative, that the vagueness doctrine should be “limited to case-by-case
challenges to particular applications of a statute” rather than facial challenges to the statute. He continued
that even if 18 U.S.C. § 16(b) were subject to a facial vagueness challenge, courts should be permitted to
consider the “actual, underlying conduct” at issue in the case before it when assessing whether the
applicable law sufficiently captures “an unmistakable core” of criminal conduct.
Impact of Dimaya
In striking down the second prong of the federal COV definition, as incorporated in the INA, the Supreme
Court has potentially narrowed the scope of criminal offenses that would render an alien subject to
removal. In fact, courts have previously interpreted 18 U.S.C. § 16(b) to cover a wide range of offenses
such as first-degree manslaughter, attempted kidnapping, lewd and lascivious acts upon a child, sexual
assault, burglary, an d assault on a police officer. While many of these offenses may, as Justice Kagan

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suggested, still constitute removable offenses under the INA, there may be some types of criminal
conduct that would only fall within the second prong of the COV definition. Additionally, the Court’s
decision may limit the government’s ability to remove aliens convicted of domestic violence offenses, a
separate ground of removal that incorporates both prongs of the COV definition. In the wake of Dimaya,
the Department of Homeland Security asserted that the Supreme Court’s decision “significantly
undermines” the agency’s efforts to remove certain categories of aliens with violent crime convictions.
Nevertheless, an alien’s criminal conviction may still fall within 18 U.S.C. § 16(a)’s elements-based
prong of the COV definition, which remains intact after Dimaya. An alien’s criminal conviction may also
fall within the aggravated felony definition’s many other enumerated categories (e.g., murder, rape,
sexual abuse of a minor, felony theft and burglary offenses)—which likewise remain untouched by
Dimaya. And given the INA’s “intertwining coverage for serious crimes,” immigration authorities may
pursue alternative grounds of deportability for aliens who were formerly removable under the second
prong of the COV definition. Thus, while Dimaya may narrow—at least to some degree—the range of
offenses that render removability, the INA’s overall structure, in the words of Justice Kagan’s majority
opinion, still ensures that there are “many other ways to achieve that result.”
Ultimately, the Supreme Court’s conclusion that the second prong of the COV definition, as incorporated
into the INA, is unconstitutionally vague may open the door to legal challenges to other INA provisions
that sweep broadly in defining the scope of conduct that triggers removal and other adverse immigration
consequences. In addition, the Dimaya Court’s willingness to apply the constitutional prohibition of
vagueness, typically used in the review of criminal statutes, to a civil immigration law might suggest a
greater willingness to review due process claims in the immigration context—typically reviewed under a
more forgiving standard than in criminal cases—more stringently than in the past.
Further, the implications of the Supreme Court’s decision extend beyond the immigration context. As
Chief Justice Roberts noted in his dissent, 18 U.S.C. § 16’s COV definition is incorporated into many
provisions of the federal criminal code. The Court’s decision also calls into question the viability of a
related federal statute that prohibits the use of a firearm during the commission of a “crime of violence,”
and employs an identical COV definition as 18 U.S.C. § 16(b). Indeed, prior to the Dimaya ruling, the
Department of Justice had argued that an invalidation of 18 U.S.C. § 16(b) “create[s] a cloud of
uncertainty over the lawfulness of criminal prosecutions and sentencing enhancements” under federal law.
The Court’s decision may also impact non-criminal federal statutes that incorporate the COV definition,
such as a civil rights law that imposes civil liability on a person who commits a “crime of violence” based
on gender. Mindful of these implications, Justice Thomas warned in his dissent that the Court’s decision
could result in “the invalidation of scores of similarly worded state and federal statutes.”
Congress may address the vagueness concerns raised by Dimaya if it deems such recourse appropriate. As
Justice Gorsuch observed in his concurring opinion, the Court’s decision “sweeps narrowly” and “does
not forbid the legislature from acting toward any end it wishes, but only requires it to act with enough
clarity that reasonable people can know what is required of them and judges can apply the law consistent
with their limited office.” Thus, Congress may consider amending 18 U.S.C. § 16(b) to specify
circumstances when a criminal offense carries a substantial risk of physical force. Congress may also
limit the COV definition to cover enumerated violent crimes, or perhaps modify the definition to cover
certain criminal offenses that carry specified prison sentences. Or alternatively, as Justice Gorsuch
suggested, Congress may consider adding to the enumerated crimes that fit within the INA’s aggravated
felony framework rather than amending the COV definition the framework incorporates.

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Author Information

Hillel R. Smith

Legislative Attorney

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