D entered a Food-4-Less grocery store armed with a semi-automatic pistol. D robbed the store of $250. D then committed a similar armed robbery of a Total gas station, netting about $40. D charged with two counts of violating the Hobbs Act, 18 U.S.C. § 1951, two counts of violating 18 U.S.C. § 924(c) (using or carrying a weapon during a crime of violence), and one count of violating 18 U.S.C. § 922(g)(1) (being a felon in possession of a firearm). A jury returned a guilty verdict on all counts. After voir dire, a jury with no alternates was sworn. At that point, one of the jurors noted that she had child-care responsibilities that would make it difficult for her to serve on the jury. The district court excused that juror and, without objection from either the government or D, swore in another juror. The jury found D guilty of all the charged crimes. The district court applied the Armed Career Criminal enhancement to D's sentence, based on his previous criminal history. The defendant's term of imprisonment totaled 562 months. D appealed: (1) that the jury selection procedures denied him his Sixth Amendment right to a jury drawn from a fair cross-section of the community and (2) that the unusual jury selection procedure used in this case violated the Double Jeopardy Clause of the Fifth Amendment among other issues.