⚡ 10-Second Rule
Almost anyone may testify if they saw the thing themselves and promise to tell the truth.
🧒 ELI-10 Scene
Grandma Rosa's blueberry pie vanished from the windowsill. The family holds a kitchen "trial." Six-year-old Theo may tell his story — he watched the whole thing from the porch. He just has to promise to tell the truth, in words he understands. Uncle Marco may not. He was at work and only heard gossip. Grandma Rosa can't be a storyteller either. She is the one judging the dispute. The referee never plays in the game.
⚖️ Actual Rule
FRE 601: "Every person is competent to be a witness unless these rules provide otherwise. But in a civil case, state law governs the witness's competency regarding a claim or defense for which state law supplies the rule of decision." FRE 602 adds a personal-knowledge floor: "A witness may testify to a matter only if evidence is sufficient to support a finding that the witness has personal knowledge of the matter." FRE 603 requires an "oath or affirmation to testify truthfully" given "in a form designed to impress that duty on the witness's conscience." Two people are flatly incompetent: the presiding judge (FRE 605, no objection needed to preserve the error) and a sitting juror testifying before fellow jurors (FRE 606(a)). After a verdict, FRE 606(b) bars juror testimony about "any statement made or incident that occurred during the jury's deliberations," anything's effect on a vote, or "any juror's mental processes" — but a juror may testify about extraneous prejudicial information, an improper outside influence, or a mistake in entering the verdict on the verdict form. The Supreme Court recognized an added constitutional exception for a juror's clear statements of racial bias, Peña-Rodriguez v. Colorado (2017). Child witnesses face no minimum age; the judge asks only whether the child can observe, remember, communicate, and grasp the duty to tell the truth. State Dead Man's statutes — which bar interested parties from testifying about transactions with a deceased person — have no federal counterpart but can govern in federal court through FRE 601's state-law sentence. [NJ-VARIANT: flagged for future Eli Explains NJ Law module]
ELI-10 translation: anyone with their own eyes and a real promise may testify; the judge and jurors sit out.
🔍 Ask These Questions
- Start from competency: under FRE 601, every person is presumed competent. (Everyone begins on the "allowed" list — the rules subtract, never add.)
- Does the witness have personal knowledge under FRE 602 — did they perceive the matter with their own senses? (Did they see, hear, touch, or smell it themselves, not just hear about it?)
- Did the witness give an oath or affirmation under FRE 603? (Did they make a real promise to tell the truth, in words that fit them?)
- Is the witness the presiding judge or a sitting juror? FRE 605 and 606(a) make them incompetent in that trial. (The referee and the scorekeepers can't also be storytellers.)
- Is a juror testifying after the verdict? FRE 606(b) seals deliberations unless extraneous information, outside influence, a verdict-form mistake, or clear racial bias is involved. (Jury-room talk stays locked up unless something leaked in from outside.)
- Is the witness a child? No age minimum — the judge checks capacity to remember, communicate, and understand truth-telling. (Little kids count if they know what a promise means.)
- Is this a civil claim governed by state law? State competency rules, including Dead Man's statutes, then control. (Sometimes the state's own entry rules run the courtroom door.)
⚠️ Bar Trap
Exam language: After an unfavorable verdict, a party offers a juror's affidavit stating that the jurors misunderstood the instructions, reached a compromise verdict, or even drank during deliberations. FRE 606(b) excludes all of it — those are internal deliberation matters, however troubling. Examiners also bait the mirror-image error: affidavits describing a juror's independent site visit, a smuggled news article, or a bribe attempt fall within the extraneous-information and outside-influence exceptions and are admissible.
ELI-10: What happened inside the jury room stays sealed, even the ugly stuff. But if something snuck in from outside, jurors may talk about that.
🧪 Question
In a civil action arising from an intersection collision, the jury returned a verdict for the defendant driver. The plaintiff moved for a new trial and submitted an affidavit from one juror stating that, midway through deliberations, another juror announced that he had driven to the intersection the previous evening, timed the traffic signal himself, and told the jury that the yellow light lasted six seconds — twice as long as the plaintiff's expert had testified. The defendant argues the affidavit is inadmissible.
May the court consider the juror's affidavit?
(A) No, because a juror may never testify about statements made during the jury's deliberations. (B) No, because a verdict may be impeached only with evidence that a juror lied during jury selection. (C) Yes, because the affidavit describes extraneous prejudicial information improperly brought to the jury's attention. (D) Yes, because any juror misconduct that likely changed the outcome is admissible to impeach the verdict.
Answer: (C). The juror's private experiment injected outside facts into deliberations. FRE 606(b)(2) expressly permits juror testimony about extraneous prejudicial information improperly brought to the jury's attention, so the affidavit is admissible on that narrow point.
💡 Why the Wrong Answers Are Wrong
- (A) overstates the ban; FRE 606(b)(2) carves out exceptions, and a juror's outside investigation fits squarely within them.
- (B) invents a rule; dishonesty during jury selection is a separate doctrine, not the exclusive path to challenging a verdict.
- (D) states an outcome-based test that does not exist; purely internal misconduct stays sealed no matter how harmful.
- ELI-10: The misconception is thinking the jury-room seal is total, or breaks whenever a verdict looks unfair. The seal has three small doors, and all of them face outside.
