D was the Vice President and General Counsel of the Chicago Truck Drivers, Helpers, and Warehouse Workers Union (Independent). D used his control over the union's investments to enrich himself and his co-conspirators through kickbacks. D was tried and convicted on a second jury trial. The presentence investigation report prepared by the probation office recommended that the convictions for labor racketeering, money laundering, and tax evasion be grouped together. P insisted that the money laundering counts could not be grouped with the other counts. The court agreed with P. In the trial court, D's attorneys did not submit papers or offer extensive oral arguments contesting the no-grouping argument. By not grouping, D's offense level was increased by two levels, yielding a concomitant increase in the sentencing range. D was sentenced to 84 months. On appeal, the attorneys again did not raise the grouping issue. A short time after argument on D's appeal, a different panel of the Seventh Circuit held that, under some circumstances, the grouping of money laundering offenses with other counts was proper under § 3D1.2. The court affirmed D's conviction and sentence. D filed a pro se motion to correct his sentence under 28 U.S.C. § 2255 claiming ineffective assistance. The District Court denied the motion, holding that an increase of 6 to 21 months was not significant enough to amount to prejudice for purposes of Strickland. On appeal, P argued only that D had not suffered prejudice within the meaning of Strickland. The court of appeals affirmed and the Supreme Court granted certiorari.