Stepfon Killingsworth pleaded guilty to one count of possessing cocaine base (crack cocaine) with the intent to distribute it, see 21 U.S.C. § 841(a)(1), (b)(1)(B). He appeals his sentence, arguing that the district court erred in cаlculating his offense level based on relevant conduct that he contested at a pre-sentencing evidentiary hearing before the district court. We affirm.
Ronald Williams pleaded guilty to one count оf conspiring to distribute crack cocaine, see 21 U.S.C. §§ 841(a)(1), (b)(1)(A), 846, and one count of distributing it, see 21 U.S.C. § 841(a)(1), (b)(1)(A). He challenges the validity of his guilty plea, the district court’s calculation of the applicable United States Sentencing Guidelines range, and the constitutionality of his sentence. We affirm his guilty-plea conviction, but we vacate his sentence and remand to the district court for resentencing.
I.
For purposes of sentencing Mr. Killingsworth, thе district court attributed to him a larger drug quantity than the amount to which he pleaded guilty to possessing. The district court derived the larger quantity from Mr. Killingsworth’s criminal activity jointly undertaken with Mr. Williams, which under U.S.S.G. *763 § IB 1.3 is relevant conduct that must be included when calculating Mr. Killings-worth’s base offense level. The district court also declined to grant Mr. Killings-worth a minor-participant reduction in his offense level, see U.S.S.G. § 3B1.2(b).
Although Mr. Killingsworth asserts that the district court lacked sufficiеnt evidence to support its findings, the district court did not err. The record contains evidence that Mr. Williams did not complete one drug transaction with a government informant until after Mr. Killingsworth arrived on the scene with the drugs; that Mr. Killingsworth went to Mr. Williams’s apartment building following another drug transaction between Mr. Williams and the informant and drove Mr. Williams around the block before dropping him off back at his apartment building; that Mr. Killings-worth told the informant to call him after the informant inquired about future drug transactions; and that a search of Mr. Killingsworth’s apartment produced a digital scale, crack cocaine, and powder cocaine.
Further, Mr. Williams testified at his change-of-plea hearing that Mr. Kill-ingsworth was one of his sources of drugs, that he conspired with Mr. Killingsworth to sell crack cocaine, and that Mr. Killings-worth worked with a third co-conspirator, Alvin Lockridge, who also supplied Mr. Williams with drugs. Additionally, telephone records reveal that Mr. Killings-worth communicated frequently with Messrs. Lockridge and Williams around the time of drug transactions between Mr. Williams and the informant. Although when called аs a witness at Mr. Killings-worth’s pre-sentencing evidentiary hearing Mr. Williams contradicted the testimony that he had given at his change-of-plea hearing, the district court found Mr. Williams’s subsequent testimony incredible. A district court’s assessment of a witness’s credibility is almost never clear error given that court’s comparative advantage at evaluating credibility.
See United States v. Adipietro,
Overall, the district court had sufficient facts to find by a preponderance of the evidence,
see United States v. Petersen,
Finally, Mr. Killingsworth maintains that the district court violated his sixth amendmеnt rights by finding facts that increased his sentence beyond the range that would have applied had the court taken into account only the facts admitted to in his plea agreement.
See United States v. Booker,
— U.S. —,
II.
A.
Mr. Williams was charged in the same bill of indictment as was Mr. Kill-ingsworth, but Mr. Williams entered into a separate plea agreement with the government. He attacks the validity of his guilty plea, arguing that, had he not pleaded guilty, he would have had a sixth amendment right to a jury’s determination of every element of his offense beyond a reasonable doubt, including drug quantity. Because the district court failed to inform him of his alleged right to have a jury determine drug quantity, he contends that his guilty plea was not knowing and voluntary.
See United States v. Perez,
B.
Mr. Williams also assigns several errors regarding his sentence. He asserts first that the district court erred when it increased his offense level for obstructing justice,
see
U.S.S.G § 3C1.1. Relying on
United States v. Dunnigan,
Mr. Williams also contends that his perjury cannot give rise to an obstruction-of-justice adjustment since the perjury occurred in a proceeding that involved another defendant,
i.e.,
Mr. Killingsworth’s pre-sentencing evidentiary hearing. The sentencing guideline that mandates an adjustment for obstructing justice requires that obstructive conduct that “related to ... a closely related offense” also occur “during the course of the investigation, prosecution, or sentencing of the instant offense of conviction.” U.S.S.G. § 3C1.1. Although this latter phrase could plausibly be read to exclude obstructive conduct in a proceeding not involving Mr. Williams, an application note to § 3C1.1, as well as the sentencing commission’s stated “[r]eason
*765
for” adding the note and otherwise amending § 3C1.1 in 1998, clarify that the phrase “during the course” is merely a temporal constraint.
See
U.S.S.G. § 3C1.1, comment. (n.l); U.S.S.GApp. C., amend. 581 (reason for amend.). We agree with the conclusion that, as long as the “investigation, prosecution, or sentencing of the instant offense of conviction” is ongoing,
see
U.S.S.G. § 3C1.1, the adjustment “would apply if the defendant obstructed justice in a co-defendant’s case.”
United States v. Burke,
Mr. Williams next asserts that the district court erred in denying him a two-level reduction for acceptance of responsibility,
see
U.S.S.G. § 3E1.1. When a district court enhances a defendant’s sentence for obstructing justice, the court may reduce that defendant’s sentence for acceptance of responsibility only in “extraordinary cases.”
Id.
at comment: (n.4). The defendant did admit to his role in the offense to which he pleaded guilty, but he perjured himself in an аttempt to exonerate one of his co-conspirators. Our court previously has held that a defendant who perjures himself at trial by taking sole responsibility for conduct that gave rise to charges against him and his co-defendants does not present an extraordinary case meriting a reduction for acceptance of responsibility simultaneous with an enhancement for obstructing justice.
See United States v. Molina,
Finally, Mr. Williams argues for the first time on appeal that the district court violated his sixth amendment rights by sentencing him under the guidelines and by finding facts that enhancеd his sentence. As was the case with. Mr. Kill-ingsworth, to obtain plain-error relief Mr. Williams must “demonstrate[ ] a reasonable probability” that he would have received a lesser sentence if he had been sentenсed under the advisory-guidelines scheme set out in
Booker. See Pirani,
Mr. Williams still cannot obtain plain-error relief, however, if the district court’s error did not “ ‘seriously affect[ ] the fairness, integrity, or public reputation of judicial proceedings.’ ”
United States v. Olano,
III.
We affirm Mr. Killingsworth’s sentence and Mr. Williams’s guilty plea, but we vacate Mr. Williams’s sentence and remand to the district court for resentencing under Booker.
