A challenge for cause is a request to the trial judge to remove a prospective juror because a specific, stated reason shows that person cannot serve fairly. The attorney has to name the ground and persuade the judge; the judge, not the lawyer, makes the call. There is no cap on how many jurors either side can strike this way, which is why it does most of the real work of clearing a jury panel of people who shouldn’t be on it.
How It Differs From a Peremptory Strike
Both tools remove jurors during selection, but they run on opposite rules. A cause challenge needs a legal reason and a judge’s ruling. A peremptory strike needs neither — the attorney simply uses one and the juror is gone. The tradeoff is supply. Peremptories are rationed; cause challenges are unlimited.1United States Courts. Participate in the Judicial Process – Rule of Law
In federal civil cases, each side gets three peremptories.2Office of the Law Revision Counsel. 28 USC 1870 – Challenges Federal criminal cases give 20 per side in death-penalty cases, 6 to the prosecution and 10 to the defense in other felonies, and 3 per side in misdemeanors.3Justia. Federal Rules of Criminal Procedure Rule 24 – Trial Jurors Every juror you can remove for cause saves a peremptory for someone you can’t. That is the practical reason attorneys press cause challenges hard even when a peremptory would be easier.
Grounds for Removing a Juror for Cause
Courts recognize three main categories: statutory disqualification, implied bias, and actual bias. Each rests on a different kind of proof, and the category you’re arguing shapes what you need to show the judge.
Statutory Disqualification
Federal law sets baseline eligibility. A person is disqualified from serving on a federal jury if they are not a U.S. citizen at least eighteen years old who has lived in the judicial district for at least one year. Anyone who cannot read, write, speak, or understand English well enough to follow the case is ineligible, as is anyone with a mental or physical condition that would prevent satisfactory service. A pending charge for a crime carrying more than a year in prison disqualifies a juror, and so does a conviction for such a crime where civil rights haven’t been restored.4Office of the Law Revision Counsel. 28 USC 1865 – Qualifications for Jury Service
These are objective boxes. You don’t have to prove the juror would be biased. Missing any requirement is enough. Juror questionnaires often flag these problems before oral questioning even starts.
Implied Bias
Implied bias exists when a juror’s connection to the case or the people in it is so close that the law simply presumes unfairness, no matter what the juror says about their own state of mind. The Supreme Court has described this as bias “conclusively presumed as matter of law.”5Legal Information Institute. A Jury Free from Bias
Classic examples: a juror related by blood or marriage to a party, a victim, or a witness; a juror who owns stock in a corporate party; a juror who is currently employed by a party or is in litigation with one. The judge doesn’t need to ask whether such a person can be fair. The relationship itself is disqualifying.
Actual Bias
Actual bias is harder to prove because it lives in the juror’s head. It exists when a juror holds opinions so fixed that they cannot set them aside and decide the case on the evidence.5Legal Information Institute. A Jury Free from Bias The proof has to come from the juror’s own words.
A juror who says they’ve already decided the defendant is guilty because of what they read in the news is the textbook case. So is one who says they distrust a particular group and can’t give a member of that group a fair hearing. The strongest foundation for the challenge is what lawyers call an unrehabilitated admission: the juror says clearly that they can’t be fair, and they hold that answer when pressed. Judges weigh demeanor here alongside the words, so how a juror answers matters as much as what they say.
Death Qualification in Capital Cases
Capital cases add a further ground that doesn’t exist in other trials. Under Wainwright v. Witt, either side may challenge a juror whose views on the death penalty would “prevent or substantially impair” their ability to follow the court’s instructions. The juror doesn’t have to say they would automatically vote one way. The judge just needs a definite impression that the person could not faithfully apply the law.6Legal Information Institute. Death Penalty and Requirement of Impartial Jury
The rule cuts both ways. The prosecution can strike jurors who could never impose death; the defense can strike jurors who could never seriously consider a lesser sentence. Wrongly excluding a juror who could fairly weigh both outcomes is reversible error.6Legal Information Institute. Death Penalty and Requirement of Impartial Jury
How to Raise the Challenge During Voir Dire
Timing controls everything. A challenge for cause must be raised during voir dire, before the jury is sworn in. Once the panel takes the oath, the window closes.
The record is the second thing to get right. The judge rules on what the transcript shows, so the answers that support the challenge have to be spoken out loud and captured by the court reporter. Open-ended questions do most of the work. “Tell me about any experiences you’ve had with law enforcement” produces more usable material than “Can you be fair?” If a juror discloses a relationship to a party or a similar experience of their own, the disclosure needs to be drawn out in full on the record.
Attorneys typically raise the challenge at a sidebar so the rest of the panel doesn’t hear the argument. In complex cases the challenge may be made in a written motion citing specific transcript passages. Either way, the judge then decides — often after the judge or opposing counsel asks the juror follow-up questions to see whether they can credibly commit to setting their views aside. A juror who initially expressed strong feelings but then genuinely agrees to follow the law may survive. A vague later promise to “try to be fair” does not automatically wipe out earlier statements; the judge weighs the whole exchange, including demeanor.
If the judge grants the challenge, the juror is excused on the spot. If the judge denies it, the attorney has to decide whether to spend a peremptory strike on that juror or leave them on the panel and preserve the issue.2Office of the Law Revision Counsel. 28 USC 1870 – Challenges
What Happens When the Judge Denies the Challenge
A denied cause challenge forces a tactical choice. The instinct is to burn a peremptory and move on. That has consequences.
In federal court, the Supreme Court held in United States v. Martinez-Salazar that a defendant is not required to use a peremptory to fix the judge’s mistake. The juror can be left on the panel, and if the defendant is convicted, the denial can be argued on appeal as a violation of the Sixth Amendment right to an impartial jury. But if you spend a peremptory on that juror and the seated jury turns out to be impartial, showing you were harmed becomes much harder. The Court reasoned that a defendant tried by an actually impartial jury has not been deprived of a constitutional right, even if the road there was uneven.7Legal Information Institute. United States v. Martinez-Salazar
State rules vary. Some states require you to exhaust your peremptories and show that a biased juror actually sat before they’ll hear the appeal. Knowing your jurisdiction’s rule matters before selection begins, not after. Appellate courts review a trial judge’s cause ruling for abuse of discretion and give heavy deference to the judge’s read on the juror’s demeanor, so the fight is much easier to win at the trial-court level than on appeal.
When a Juror Lies and It Comes Out Later
Some problems don’t surface until after the verdict. A juror who hid a relationship to a witness, buried a relevant personal experience, or misrepresented their ability to be fair can become grounds for a new trial, but only under the test set in McDonough Power Equipment v. Greenwood. The party seeking a new trial has to show two things: that the juror failed to answer a question honestly, and that a truthful answer would have supported a valid cause challenge.8Legal Information Institute. McDonough Power Equipment, Inc. v. Greenwood, 464 U.S. 548 (1984)
Both prongs matter. If the question was never asked, the juror’s silence is not dishonesty. And even a clear lie won’t reopen a case unless it was about something that would have gotten the juror struck for cause. The quality of the questions asked during selection defines what counts as a dishonest omission later. Federal courts have also warned that jurors who intentionally lie during questioning can face serious consequences of their own, including contempt of court.9U.S. District Court: Southern District of New York. The Voir Dire Examination