United States v. Carlton Williams, 898 F.3d 323

DEA task force placed a GPS on Carlton Williams's car after controlled buys indicated he procured Detroit-sourced heroin and sold in Pittsburgh; officers tracked a January 11, 2013 trip to Detroit and back.
Pennsylvania State Police Trooper Volk stopped Williams for speeding, issued a citation, and obtained Williams's written consent to search the car; consent was uncontested as initially voluntary.
Troopers searched the vehicle for ~71 minutes, including passenger compartment, trunk, undercarriage, and disassembled speakers; a K‑9 was requested; officers inspected cell phones (one was password‑protected) and read texts from the other.
Williams made statements expressing impatience and protested certain searches (speakers, phones), at one point saying officers needed a warrant; he also allegedly said they had searched his car "three times" and he had to go — the court found that testimony only partially credible and no evidence that Volk heard it.
Troopers continued searching and found 39 grams of heroin in a sleeve covering the parking‑brake lever; Williams was arrested, pleaded guilty to possession with intent to distribute, reserved right to appeal suppression and career‑offender designation, and was sentenced.

Issue	Plaintiff's Argument (Williams)	Defendant's Argument (Government)	Held
1) Motion to suppress: whether consent was withdrawn or coerced	Williams argues he revoked consent during the lengthy search (statements of impatience and protest) and that coercive circumstances prevented effective withdrawal	Government argues consent remained voluntary and no unequivocal withdrawal occurred; officers honored limitations Williams asserted re: speakers/phones	Court held consent may be withdrawn but Williams did not unequivocally withdraw it; consent was voluntary and not coerced, so suppression denied
2) Career‑offender enhancement under U.S.S.G. §4B1.1: whether 1998 RICO conviction qualifies as a "controlled substance offense"	Williams contends the RICO conviction (18 U.S.C. §1962(c)) is broader than the Guidelines' generic definition and therefore cannot count as a predicate controlled‑substance offense	Government relies on the modified categorical approach to show Williams's plea/admissions established predicate acts that were federal drug offenses (§841/§846), fitting the Guidelines' definition	Court applied the modified categorical approach, found Williams admitted multiple §841/§846 predicate acts, and held the RICO conviction counts as a prior controlled‑substance offense for the career‑offender enhancement

Schneckloth v. Bustamonte, 412 U.S. 218 (consent must be voluntary for Fourth Amendment purposes)
Florida v. Jimeno, 500 U.S. 248 (scope of consent measured by objective reasonable person standard)
Walter v. United States, 447 U.S. 649 (scope of a search limited by authorization)
Taylor v. United States, 495 U.S. 575 (categorical approach for determining whether prior convictions qualify)
Descamps v. United States, 570 U.S. 254 (limits on comparing statutory elements; modified categorical approach rules)
Mathis v. United States, 136 S. Ct. 2243 (further delineation of divisible statutes and use of the modified categorical approach)