1
(Slip Opinion)
OCTOBER TERM, 2008
Syllabus
NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
being done in connection with this case, at the time the opinion is issued.
The syllabus constitutes no part of the opinion of the Court but has been
prepared by the Reporter of Decisions for the convenience of the reader.
See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.
SUPREME COURT OF THE UNITED STATES
Syllabus
CHAMBERS v. UNITED STATES
CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
THE SEVENTH CIRCUIT
No. 06–11206. Argued November 10, 2008—Decided January 13, 2009
The Armed Career Criminal Act (ACCA) imposes a 15-year mandatory
prison term on a felon unlawfully in possession of a firearm who has
three prior convictions for committing certain drug crimes or “a vio-
lent felony,” 18 U. S. C. §924(e)(1), defined as a crime punishable by
more than one year’s imprisonment that, inter alia, “involves conduct
that presents a serious potential risk of physical injury to another,”
§924(e)(2)(B)(ii). At petitioner Chambers’ sentencing for being a felon
in possession of a firearm, the Government sought ACCA’s 15-year
mandatory prison term. Chambers disputed one of his prior convic-
tions—failing to report for weekend confinement—as falling outside
the ACCA definition of “violent felony.” The District Court treated
the failure to report as a form of what the relevant state statute calls
“escape from [a] penal institution,” and held that it qualified as a
“violent felony” under ACCA. The Seventh Circuit agreed.
Held: Illinois’ crime of failure to report for penal confinement falls out-
side the scope of ACCA’s “violent felony” definition. Pp. 3–8.
(a) For purposes of ACCA’s definitions, it is the generic crime that
counts, not how the crime was committed on a particular occasion.
Taylor v. United States, 495 U. S. 575, 602. This categorical ap-
proach requires courts to choose the right category, and sometimes
the choice is not obvious. The nature of the