Source: http://masslitapp.com/html/Federal_Rules_of_Criminal_Procedure/062017/Federal_Rules_of_Criminal_Procedure_062017Rule_24.html
Timestamp: 2019-04-25 22:17:32+00:00

Document:
Note to Subdivision (a). This rule is similar to Rule 47(a) of the Federal Rules of Civil Procedure [28 U.S.C., Appendix] and also embodies the practice now followed by many Federal courts in criminal cases. Uniform procedure in civil and criminal cases on this point seems desirable.
Note to Subdivision (b). This rule embodies existing law, 28 U.S.C. 424 [now 1870] (Challenges), with the following modifications. In capital cases the number of challenges is equalized as between the defendant and the United States so that both sides have 20 challenges, which only the defendant has at present. While continuing the existing rule that multiple defendants are deemed a single party for purposes of challenges, the rule vests in the court discretion to allow additional peremptory challenges to multiple defendants and to permit such challenges to be exercised separately or jointly. Experience with cases involving numerous defendants indicates the desirability of this modification.
Note to Subdivision (c). This rule embodies existing law, 28 U.S.C. [former] 417a (Alternate jurors), as well as the practice prescribed for civil cases by Rule 47(b) of the Federal Rules of Civil Procedure [28 U.S.C., Appendix], except that the number of possible alternate jurors that may be impaneled is increased from two to four, with a corresponding adjustment of challenges.
Experience has demonstrated that four alternate jurors may not be enough for some lengthy criminal trials. See e.g., United States v. Bentvena, 288 F.2d 442 (2d Cir. 1961); Reports of the Proceedings of the Judicial Conference of the United States, 1961, p. 104. The amendment to the first sentence increases the number authorized from four to six. The fourth sentence is amended to provide an additional peremptory challenge where a fifth or sixth alternate juror is used.
The words “or are found to be” are added to the second sentence to make clear that an alternate juror may be called in the situation where it is first discovered during the trial that a juror was unable or disqualified to perform his duties at the time he was sworn. See United States v. Goldberg, 330 F.2d 30 (3rd Cir. 1964), cert. den. 377 U.S. 953 (1964).
As currently written, Rule 24(c) explicitly requires the court to discharge all of the alternate jurors—who have not been selected to replace other jurors—when the jury retires to deliberate. That requirement is grounded on the concern that after the case has been submitted to the jury, its deliberations must be private and inviolate. United States v. Houlihan, 92 F.3d 1271, 1285 (1st Cir. 1996), citing United States v. Virginia Election Corp., 335 F.2d 868, 872 (4th Cir. 1964).
Rule 23(b) provides that in some circumstances a verdict may be returned by eleven jurors. In addition, there may be cases where it is better to retain the alternates when the jury retires, insulate them from the deliberation process, and have them available should one or more vacancies occur in the jury. That might be especially appropriate in a long, costly, and complicated case. To that end the Committee believed that the court should have the discretion to decide whether to retain or discharge the alternates at the time the jury retires to deliberate and to use Rule 23(b) to proceed with eleven jurors or to substitute a juror or jurors with alternate jurors who have not been discharged.
In order to protect the sanctity of the deliberative process, the rule requires the court to take appropriate steps to insulate the alternate jurors. That may be done, for example, by separating the alternates from the deliberating jurors and instructing the alternate jurors not to discuss the case with any other person until they replace a regular juror. See, e.g., United States v. Olano, 507 U.S. 725 (1993) (not plain error to permit alternate jurors to sit in during deliberations); United States v. Houlihan, 92 F.3d 1271, 1286–88 (1st Cir. 1996) (harmless error to retain alternate jurors in violation of Rule 24(c); in finding harmless error the court cited the steps taken by the trial judge to insulate the alternates). If alternates are used, the jurors must be instructed that they must begin their deliberations anew.
Finally, subsection (c) has been reorganized and restyled.
GAP Report—Rule 24(c). The final sentence of Rule 24(c) was moved from the committee note to the rule to emphasize that if an alternate replaces a juror during deliberations, the court shall instruct the jury to begin its deliberations anew.
The language of Rule 24 has been amended as part of the general restyling of the Criminal Rules to make them more easily understood and to make style and terminology consistent throughout the rules. These changes are intended to be stylistic only, except as noted below.
In restyling Rule 24(a), the Committee deleted the language that authorized the defendant to conduct voir dire of prospective jurors. The Committee believed that the current language was potentially ambiguous and could lead one incorrectly to conclude that a defendant, represented by counsel, could personally conduct voir dire or additional voir dire. The Committee believed that the intent of the current provision was to permit a defendant to participate personally in voir dire only if the defendant was acting pro se. Amended Rule 24(a) refers only to attorneys for the parties, i.e., the defense counsel and the attorney for the government, with the understanding that if the defendant is not represented by counsel, the court may still, in its discretion, permit the defendant to participate in voir dire. In summary, the Committee intends no change in practice.
Finally, the rule authorizes the court in multi-defendant cases to grant additional peremptory challenges to the defendants. If the court does so, the prosecution may request additional challenges in a multi-defendant case, not to exceed the total number available to the defendants jointly. The court, however, is not required to equalize the number of challenges where additional challenges are granted to the defendant.

References: v. 
 v. 
 v. 
 v. 
 v. 
 v.