Fed. R. Evid. 606

Juror’s Competency as a Witness

(a) At the Trial.

A juror may not testify as a witness before the other jurors at the trial. If a juror is called to testify, the court must give a party an opportunity to object outside the jury’s presence.

(b) During an Inquiry into the Validity of a Verdict or Indictment.

(1)

Prohibited Testimony or Other Evidence. During an inquiry into the validity of a verdict or indictment, a juror may not testify about any statement made or incident that occurred during the jury’s deliberations; the effect of anything on that juror’s or another juror’s vote; or any juror’s mental processes concerning the verdict or indictment. The court may not receive a juror’s affidavit or evidence of a juror’s statement on these matters.

(2)

Exceptions. A juror may testify about whether:

(A)

extraneous prejudicial information was improperly brought to the jury’s attention;

(B)

an outside influence was improperly brought to bear on any juror; or

(C)

a mistake was made in entering the verdict on the verdict form.

( Pub. L. 93–595, § 1 , Jan. 2, 1975 , 88 Stat. 1934 ; Pub. L. 94–149, § 1(10) , Dec. 12, 1975 , 89 Stat. 805 ; Mar. 2, 1987 , eff. Oct. 1, 1987 ; Apr. 12, 2006 , eff. Dec. 1, 2006 ; Apr. 26, 2011 , eff. Dec. 1, 2011 .)