Sessions v. Dimaya: Why the Supreme Court Struck Down 18 U.S.C. § 16(b)

Update (October 2026): The Supreme Court decided Sessions v. Dimaya on April 17, 2018. By a 5-4 vote, it held that the "residual clause" in 18 U.S.C. § 16(b) is unconstitutionally vague. A year later, in United States v. Davis (2019), the Court struck down the similar residual clause in 18 U.S.C. § 924(c)(3)(B). After Davis, a § 924(c) gun charge must rest on a crime that has the use, attempted use, or threatened use of force as an element, or on a drug trafficking crime.

We first wrote this post in June 2017, while we were waiting for the Supreme Court's decision in Sessions v. Dimaya, No. 15-1498. (The case name changed from Lynch to Sessions when the Attorney General changed.) The background below explains what was at stake.

The question was whether 18 U.S.C. § 16(b) is unconstitutional after the Court's 2015 decision in Johnson v. United States. Johnson struck down the residual clause of the Armed Career Criminal Act as unconstitutionally vague, meaning too unclear to give fair notice of what it covers.

What § 16 says

Section 16 gives a general definition of "crime of violence." It applies when another law uses that term without defining it. It has two parts:

(a) an 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 the offense.

Section 16(a) is called the "force clause" or "elements clause." It was not at issue in Dimaya. If an offense counts as a "crime of violence" under the force clause, courts generally do not reach whether § 16(b) also applies.

Section 16(b) is called the "residual clause." It is very close to the ACCA clause the Court struck down in Johnson.

An immigration case with criminal consequences

Dimaya was an immigration case, not a criminal case. When we wrote this post, it was unclear whether that would matter to the Court's analysis, and the justices discussed the point at oral argument in January 2017. We expected a decision by the end of the Court's term in June 2017. Instead, the Court ordered the case reargued in October 2017 and decided it in April 2018. In the end, the Court held that the same strict vagueness standard applied, and § 16(b) fell.

Could this affect your case?

If you were convicted or sentenced under a residual clause, a lawyer can review whether Johnson, Dimaya, or Davis affects your case. Timing matters. A motion to vacate a federal sentence under 28 U.S.C. § 2255 generally must be filed within one year of the latest of several trigger dates, including the date the Supreme Court first recognized a new right that applies retroactively. 28 U.S.C. § 2255(f). Many of those deadlines have passed, but each case is different, and other paths may remain.

Facing a federal sentence? Book a consultation to talk it through with Brandon Sample.