¶1This is the direct appeal of the defendant-appellant, Steven Schwan (“Schwan”), after a Superior Court jury convicted him of two counts of Unlawful Sexual Contact in the Second Degree, and a bench trial resulted in an additional conviction for Unlawful Sexual Conduct by a Sex Offender Against a Child. Schwan raises one argument on appeal: that the trial judge committed reversible error by not excluding, for cause, a juror who was acquainted with a prosecutor, although that same prosecutor was not involved in Schwan’s case.
¶2We have concluded that the trial judge erred by failing to exclude the juror, in the absence of a determination that the juror could render a fair and impartial verdict. Because Schwan’s Sixth Amendment right to a fair trial by an impartial jury was violated, his convictions must be reversed.
¶3Basic Facts
¶4On June 3, 2011, Schwan’s daughter invited two minor friends to her house to watch movies. Schwan joined the three girls to watch the movies in his daughter’s bedroom. During the movie, Schwan joined the girls on the bed. A.P.,
¶5Schwan was charged by indictment with Rape in the Second Degree,
¶6At trial, all three minor females testified. The jury acquitted Schwan of Rape in the Second Degree, Rape in the Fourth Degree, and both counts of Providing Alcohol to a Minor. The jury did, however, find Schwan guilty of two counts of the lesser included crime of Unlawful Sexual Contact in the Second Degree.
¶7*586Facts Regarding Juror 11
¶8During the voir dire of the petit jury, the trial judge asked the now-standard question, “Do you know the attorneys in this case, or any other attorney or employee in the offices of the Attorney General or defense counsel?” (emphasis added). Eventual Juror 11, the juror in question in this appeal, did not respond that she knew a non-trial prosecutor. Accordingly, defense counsel had no reason to move to exclude Juror 11 at that time she was seated.
¶9Without using his full complement of peremptory challenges allowable by court rule,
¶10The following day, before the beginning of any proceedings, the trial prosecutor notified the judge about a potential conflict with the person seated as Juror 11. Through other members in the Attorney General’s office, the trial prosecutor discovered that Juror 11 had a connection to another prosecutor who was not involved with Schwan’s trial (the “non-trial prosecutor”). The trial prosecutor also learned that Juror 11 was specifically told by the non-trial prosecutor, sometime before being selected for the jury, that if she [Juror 11] was selected to serve on a jury, that she should reveal her connection to the non-trial prosecutor to the court during voir dire.
¶11The trial judge decided to make inquiries of Juror 11 in the presence of counsel. Juror 11 was individually brought into the courtroom — still prior to any trial proceedings — to ascertain her connection to the non-trial prosecutor. The trial judge asked Juror 11 if she knew any of the attorneys in Schwan’s case, or any attorneys in the Office of the Attorney General. This time, Juror 11 answered affirmatively. The trial judge suggested, and Juror 11 agreed, that she had misinterpreted the question during voir dire. Juror 11 said she thought the initial question during voir dire related only to attorneys involved in Schwan’s case.
¶12Juror 11 stated that she knew the non-trial prosecutor because Juror 11 was the director of the childcare center where the non-trial prosecutor takes her children. Thus, the juror and the non-trial prosecutor were in an ongoing business relationship. The trial judge then specifically asked Juror 11 if she had ever spoken to the non-trial prosecutor about being called for jury duty. Juror 11 denied ever having spoken to the non-trial prosecutor about that topic. Juror 11 was then excused from the courtroom.
¶13Defense counsel made its first application to have Juror 11 removed. In addition to the connection to the non-trial prosecutor, defense counsel expressed concern that Juror 11 was untruthful when specifically asked about prior conversations with the non-trial prosecutor about being called for jury duty. Defense counsel stated, “it’s a little troubling to me that a pretty clear jury voir dire question was read, and it appears she had been instructed beforehand to come forward, and she didn’t, and upon questioning by the [c]ourt, she denied being instructed to do that.” In denying defense counsel’s application, the trial judge stated that “the [c]ourt does not believe that there’s a basis for cause to remove the juror, so the application is denied.”
¶14Following the trial judge’s refusal to remove Juror 11 for cause, defense counsel suggested, “[Pjerhaps it might be appro*587priate to ask [the non-trial prosecutor] if she remembers having a conversation with that juror or with someone who works at the daycare facility about that.” The trial judge agreed to ask the non-trial prosecutor if she had spoken to Juror 11 about serving on a jury. Before the non-trial prosecutor was located, defense counsel renewed the application to have Juror 11 removed. Defense counsel suggested that “[t]he defense still has peremptory challenges left if the [c]ourt will be willing to consider one of those being used to remove this juror and replace with an alternate.” The trial prosecutor responded, “I don’t think that’s proper.” The trial judge agreed: “That’s not proper.... You indicated you were content with the jury. That solves that issue.”
¶15The non-trial prosecutor was then located and brought into the courtroom. She stated that she had spoken to Juror 11 more than a week before, shortly after Juror 11 received the notification about being summoned for jury duty. At that time, the non-trial prosecutor told Juror 11 that “she should mention that she knows me because I know that that’s generally one of the [c]ourt’s questions in a criminal trial, and I know sometimes that confuses people when the questions are asked. So I said make sure that you tell them that you know me if you get called and you’re asked that question.”
¶16After the non-trial prosecutor was excused, the trial prosecutor responded to the trial judge’s inquiry on whether this “clear[ed] the air a little bit.” The trial prosecutor said: “I think it completes the record and it makes it easier to make the decision. I don’t see this being a situation where we have somebody who is well-acquainted with [the non-trial prosecutor]. And if she says she’s not biased in any way, I have no problem with her remaining.” Defense counsel then made his third application to have Juror 11 removed, not only on grounds of potential' bias, but also because Juror 11 had not been forthcoming about her prior conversations with the non-trial prosecutor. Defense counsel argued:
Well, Your Honor, I don’t think the issue is whether the juror is well-acquainted with [the non-trial prosecutor] or not. I think it’s pretty clear she is not. The issue is whether the juror was told/informed by [the non-trial prosecutor] that when you’re called for jury duty, you need to tell the [c]ourt that you know me. She was told that. I happen to believe [the non-trial prosecutor]’s recollection of the events. The juror plainly stated that never happened. That’s an issue for the defense. Defense renews the application for removal.
¶17The trial judge responded that “[b]ased upon the comments that [the non-trial prosecutor] made to help clarify the issue, I’m confident that my earlier decision is correct. The motion is denied. This juror will not be removed for cause.”
¶18ImpaHial Jury Mandate
¶19Under the Sixth Amendment of the United States Constitution,
¶20“Voir dire is the historic method used to identify bias in prospective jurors and is critical to protecting a defendant’s right to a fair trial by an impartial jury.”
¶21When the trial has started, however, if a potential for juror bias is discovered, the challenge for cause is the defendant’s only option for relief. Peremptory challenges are a “jury selection tool [that] have historically and uniformly been limited to the pre-trial jury selection process.”
¶22*589This case presents the unusual scenario where potential juror bias is discovered after voir dire but before the jury trial has actually started. Since the jury had been sworn in Schwan’s case, however, jeopardy had attached.
¶23Challenge For Cause
¶24Historically, the decision to keep or exclude a prospective juror — or an impaneled juror — who is challenged for cause rests in the sound discretion of the trial judge.
[T]hat upon the trial of the issue of fact raised by a challenge for such cause the court will practically be called upon to determine whether the nature and strength of the opinion formed are such as in law necessarily to raise the presumption of partiality. The question thus presented is one of mixed law and fact, and to be tried, as far as the facts are concerned, like any other issue of that character, upon the evidence. The finding of the trial court upon that issue ought not to be set aside by a reviewing court, unless the error is manifest.25
¶25The United States Supreme Court has not, however, established a constitutional test to determine juror partiality. Instead, the Supreme Court has stated that “[[Impartiality is not a technical conception. It is a state of mind.... [and] the Constitution lays down no particular tests and procedure is not chained to any ancient and artificial formula.”
¶26Delaware’s Voir Dire Requirements
¶27Superior Court Criminal Rule of Procedure (“Rule”) 24 explains the trial judge’s obligations during pretrial voir dire. Rule 24 states, “the court shall conduct or permit such examination as is reasonably calculated to ascertain prejudice of a juror.” During the voir dire process, the judge determines that if any individual is unable or unwilling to hear the particular case at issue fairly and impartially, that individual should be removed from the panel for cause.
¶28In Parson, a prospective juror answered that she had an opinion as to the defendant’s guilt, and that at that moment she could not presume him innocent.
It is apparent that the decision as to whether or not to excuse such a prospective juror for cause rests in the discretion of the trial judge who must determine from the witness’ testimony whether or not he feels that the statement to the effect that she could, despite her opinion, nevertheless render an impartial verdict, was satisfactory. If the trial judge believes the witness’ statement, then he may permit the individual to be drawn as a juryman.31
¶29Although Superior Court Criminal Rule of Procedure 24 only applies to voir dire during the pretrial jury selection process, we hold that those same procedures should be followed after a juror has been seated and issues about that juror’s impartiality are raised.
¶30Standard of Review
¶31A trial judge’s decision not to remove a juror for cause is ordinarily entitled to deference.
¶32In this case, the record reflects that the trial judge’s examination of Juror 11 was incomplete. Juror 11 was never asked if she could render a fair and impartial verdict, notwithstanding her ongoing business relationship with the non-trial prosecutor. Juror 11 was also never asked about the inconsistency between her representations and those of the non-trial prosecutor. Accordingly, there was no opportunity to assess Juror ll’s credibility on either of those issues. Therefore, the trial judge’s determination that Juror 11 should not be excused for cause is not entitled to deference in this appeal.
¶33Seated Juror Challenges
¶34Schwan asserts that it was reversible error for the trial judge not to remove *591Juror 11 for cause. The challenge for cause, and the investigation into potential bias, can arise in different contexts. Here, the specific context is that Juror 11 failed to disclose her connection to the prosecutors’ office during voir dire — and that connection was not discovered until after Juror 11 was seated and sworn in for Schwan’s trial. This Court’s jurisprudence on challenges for cause in this specific context is well established.
¶35The investigation into a seated juror’s potential bias, and whether that juror should then be excluded for cause, depends upon the nature of the juror’s misrepresentation during voir dire. To demonstrate reversible error in cases involving inadvertent nondisclosure, a defendant must demonstrate that “a juror failed to answer honestly a material question on voir dire,” and that “a correct response would have provided a valid basis for a challenge for cause.”
¶36The State argues that Schwan’s prosecution and Juror ll’s presence on his jury is analogous to the factual circumstances in Caldwell v. State.
¶37The facts involving the juror in Caldwell are distinguishable from Schwan’s case in two important respects. First, that jury panel was not asked if they knew any non-trial prosecutors. In Caldwell, the record reflected that the jury voir dire questions only asked, “ ‘Do you know any of the attorneys in this case....’” and did not specifically inquire about other nonparticipating attorneys in the Office of the Attorney General.
¶38The facts in Schwan’s case are more like the circumstances in- Jackson v. State,
¶39Reversal Required
¶40In this case, one of the voir dire questions was “Do you know the attorneys in this case, or any other attorney or employee in the offices of the Attorney General or the defense counsel?” Juror 11 did not respond affirmatively to that unambiguous inquiry. When Juror 11 was asked that same question the day after she was seated, her immediate response was in the affirmative. She stated that she knew a non-trial prosecutor and that she misunderstood that same question when it was asked during voir dire on the previous day. Juror 11 also denied having discussed her summons for jury duty with the non-trial prosecutor.
¶41After Juror ll’s explanation and representations, the non-trial prosecutor was questioned separately. The non-trial prosecutor completely contradicted the representations made by Juror 11 that they had never discussed the summons for jury duty. Moreover, the non-trial prosecutor said she told Juror 11 to expect the standard voir dire question that was asked in Schwan’s case and to disclose the relationship with the non-trial prosecutor.
¶42After the non-trial prosecutor was questioned, the trial judge responded that “[bjased upon the comments that [the non-trial prosecutor] made to help clarify the issue, I’m confident that my earlier decision is correct. The motion is denied. This juror will not be removed for cause.” That ruling was made after the non-trial prosecutor completely contradicted Juror ll’s representations and the trial prosecutor said “[a]nd if she [Juror 11] says she’s not biased in any way, I have no problem with her remaining.”
¶43A de novo review of the record reflects no questions were asked regarding Juror ll’s ability to be fair and impartial notwithstanding her connection to a non-trial prosecutor. Moreover, the record reflects no inquiry into the complete inconsistency between the representations of Juror 11 and the non-trial prosecutor about a conversation concerning Juror ll’s summons for jury duty. Thus, on two separate subjects, “the trial judge eschewed the opportunity to evaluate this juror’s demeanor and credibility, a crucial element in the determination of impartiality.”
¶44Therefore, as in Knox, “we must conclude that the inquiry into [Juror ll’s] objectivity was inadequate as a matter of law.”
¶45Conclusion
¶46Schwan was denied his Sixth Amendment right to a fair trial by an impartial jury. The judgments of the Superior Court are reversed and this matter is remanded for a new trial.
¶47. The complainant, a minor, has been assigned a pseudonym pursuant to Del. Supr. Ct. R. 7(d).
¶48. Del.Code Ann. tit. 11, § 772.
¶49. DeLCode Ann. tit. 11, § 777.
¶50. Code Ann. tit. 11, § 770.
¶51. Code Ann. tit. 4, § 904.
¶52. The record reflects that the jury found Schwan guilty of this lesser included charge for both Rape in the Second Degree and Rape in the Fourth Degree.
¶53. See Del. Super. Ct. Crim. R. 24.
¶54.U.S. Const, amend. VI ("In all criminal prosecutions, the accused shall enjoy the right to a speedy and public trial, by an impartial jury....’’).
¶55. Knox v. State, 29 A.3d 217, 223-24 (Del.2011).
¶56. Id.at 224 (citing Banther v. State, 823 A.2d 467, 481 (Del.2003)).
¶57. Hall v. State, 12 A.3d 1123, 1127 (Del.2010) (quoting Styler v. State, 417 A.2d 948, 951-52 (Del.1980)).
¶58. Knox v. State, 29 A.3d at 223; see also Jackson v. State, 374 A.2d 1, 2 (Del.1977).
¶59. Knox v. State, 29 A.3d at 223 (quoting Banther v. State, 823 A.2d at 481). "So delicate are the balances in weighing justice that what might seem trivial under some circumstances would turn the scales to its perversion. Not only the evil, in such cases, but the appearances of evil, if possible, should be avoided." Jackson v. State, 374 A.2d at 2-3 (quoting George P. Craig & Co. v. Pierson Lumber Co., 169 Ala. 548, 53 So. 803, 805 (1910)).
¶60. Banther v. State, 823 A.2d at 481-82; see also Diaz v. State, 743 A.2d 1166, 1172 (Del.1999); Morgan v. Illinois, 504 U.S. 719, 729, 112 S.Ct. 2222, 119 L.Ed.2d 492 (1992).
¶61. Black’s Law Dictionary 1710 (9th ed. 2009).
¶62. Hughes v. State, 490 A.2d 1034, 1041 (Del.1985) (citing Parson v. State, 275 A.2d 777, 780 (Del.1971)).
¶63. Banther v. State, 823 A.2d at 482 (citing Jackson v. State, 374 A.2d at 2). The purpose of peremptory challenges "is to permit litigants to assist the government in the selection of an impartial trier of fact.” Edmonson v. Leesville Concrete Co., 500 U.S. 614, 620, 111 S.Ct. 2077, 114 L.Ed.2d 660 (1991).
¶64. United States v. Harbin, 250 F.3d 532, 539 (7th Cir.2001). See also United States v. Martinez-Salazar, 528 U.S. 304, 316, 120 S.Ct. 774, 145 L.Ed.2d 792 (2000).
¶66. Peremptory is defined as “[n]ot requiring any shown cause.” Black’s Law Dictionary 1251 (9th ed. 2009). Batson v. Kentucky, 476 U.S. 79, 98, 106 S.Ct. 1712, 90 L.Ed.2d 69 (1986) ("[T]he peremptory challenge occupies an important position in our trial procedures.”); United States v. Harbin, 250 F.3d at *589540-41 (citing Holland v. Illinois, 493 U.S. 474, 483, 110 S.Ct. 803, 107 L.Ed.2d 905 (1990)) ("The Supreme Court has long recognized that peremptory challenges are one of the most important of the rights secured to the accused, and that the system of peremptory challenge has traditionally provided the assurance of impartiality.”).
¶67. Hughey v. State, 522 A.2d 335, 339 (Del.1987).
¶70. Reynolds v. United States, 98 U.S. 145, 25 L.Ed. 244 (1878).
¶72. United States v. Wood, 299 U.S. 123, 145-46, 57 S.Ct. 177, 81 L.Ed. 78 (1936).
¶73. Del. Super. Ct. Juror Use Standard 8, Removal from the Jury Panel for Cause:
If the judge determines during the voir dire process that any individual is unable or unwilling to hear the particular case at issue fairly and impartially, that individual should be removed from the panel. Such a determination may be made on motion of counsel or on the judge's own initiative.
¶74(Emphasis added); see also Knox v. State, 29 A.3d 217, 224 (Del.2011) (juror already seated).
¶75. Parson v. State, 275 A.2d 777 (Del.1971).
¶78. Id. at 781-82.
¶79. See Knox v. State, 29 A.3d at 224.
¶82. Id. at 220-21.
¶84. Banther v. State, 783 A.2d 1287, 1290-91 (Del.2001) (quoting McDonough Power Equip., Inc. v. Greenwood, 464 U.S. 548, 556, 104 S.Ct. 845, 78 L.Ed.2d 663 (1984)).
¶85. Jackson v. State, 374 A.2d 1, 2 (Del.1977); see also Banther v. State, 783 A.2d at 1291.
¶86. Caldwell v. State, 780 A.2d 1037, 1057-59 (Del.2001).
¶87. Id. at 1057-58.
¶88. See id. at 1059-60.
¶89. Id. at 1058 (emphasis omitted).
¶91. Jackson v. State, 374 A.2d 1 (Del.1977).
¶94. See id.
¶95. Knox v. State, 29 A.3d 217, 221 (Del.2011).
¶97. See Weber v. State, 547 A.2d 948, 954 (Del.1988).