In the Warger v. Shauers case of 2014, the U.S. Supreme Court ruled that a juror's dishonesty during voir dire (the preliminary examination of a witness or a juror by a judge or counsel) cannot be used as evidence to challenge the validity of a verdict in federal court. The case arose from an accident where petitioner Gregory Warger was injured after respondent Randy Shauers' truck collided with his motorcycle. During jury selection for this trial, one potential juror stated she could remain impartial despite her daughter's involvement in an accident shortly before trial; however, it later emerged that she had influenced other jurors based on her personal experience and bias towards accidents like these which contradicted what she said during voir dire about being able to stay unbiased. Despite this revelation, the Supreme Court held unanimously that Federal Rule of Evidence 606(b), which generally prohibits jurors from testifying about their deliberations in order to impeach their verdicts, also applies when such testimony is offered at post-verdict hearings seeking new trials.

In the Warger v. Shauers case, there was no dissenting opinion issued by any of the justices. The Supreme Court's decision was unanimous, with all participating justices agreeing that juror testimony about statements made during deliberations cannot be used to challenge a verdict in federal court under Rule 606(b) of Federal Rules of Evidence. This rule prohibits jurors from testifying about their thought processes during deliberations in an effort to impeach their own verdicts after they have been rendered.