A jury trial works by moving through a set sequence: the court seats a jury, each side gives an opening statement, the party with the burden of proof presents evidence and witnesses first and the other side follows, both sides deliver closing arguments, the judge instructs the jury on the law, and the jurors deliberate in private until they reach a verdict. The same skeleton applies whether the case is criminal or civil, in federal or state court. What changes between cases is the size of the jury, the standard of proof, and how much time each phase takes.
When a Jury Decides Your Case
The Sixth Amendment guarantees a jury in criminal cases, and in practice that right applies to serious offenses — generally those carrying a potential sentence of more than six months in jail. Minor infractions can be decided by a judge alone. Civil cases carry a separate jury right under the Seventh Amendment for suits at common law where more than $20 is in dispute, a threshold that has never been adjusted and effectively covers any civil trial.1Cornell Law School Legal Information Institute (LII). Identifying Cases Requiring a Jury Trial Either party in a civil case can demand a jury, or both can agree to a bench trial.
Federal criminal trials use 12 jurors. Federal civil trials seat between 6 and 12, and every juror who begins deliberations must take part in the verdict unless the court excuses them.2Cornell Law School Legal Information Institute (LII). Federal Rules of Civil Procedure Rule 48 – Number of Jurors, Verdict, Polling State courts vary; some use smaller juries for civil matters or misdemeanors.
Selecting the Jury
Before questioning begins, potential jurors usually complete a written questionnaire covering citizenship, residency, language ability, and criminal history — the statutory qualifications for service.3Office of the Law Revision Counsel. 28 USC 1865 – Qualifications for Jury Service In high-profile cases the questionnaire may run dozens of pages and probe media exposure, personal experiences, and attitudes tied to the case.
Voir Dire
In-person selection is called voir dire, French for “to speak the truth.” The judge and both sides’ attorneys question prospective jurors about their backgrounds, beliefs, and any connection to the case, the parties, or the witnesses. The aim is to surface bias — open or hidden — that would keep someone from deciding the case fairly. A juror who cannot set aside a strong opinion about the type of case, or who knows a witness personally, rarely survives this stage.
Challenges for Cause and Peremptory Challenges
Attorneys strike prospective jurors in two ways. A challenge for cause asks the judge to dismiss someone whose answers show actual bias or a conflict of interest, and there is no cap on how many an attorney can raise if the reasons are legitimate.4United States Courts. Participate in the Judicial Process – Rule of Law
Peremptory challenges are different. Each side gets a fixed number and can use them without stating a reason. A federal felony trial gives the defense 10 and the prosecution 6. Misdemeanor trials give each side 3. Capital cases give each side 20.5Cornell Law School Legal Information Institute (LII). Federal Rules of Criminal Procedure Rule 24 – Trial Jurors Under Batson v. Kentucky, peremptory strikes cannot be used to remove jurors because of race, ethnicity, or gender; if the pattern looks discriminatory, the striking attorney must offer a neutral explanation.4United States Courts. Participate in the Judicial Process – Rule of Law
Alternate Jurors
Federal criminal courts can seat up to six alternates who sit through the whole trial. If a regular juror is excused for illness, an emergency, or a disqualifying reason, an alternate takes over with full authority. The court can hold alternates back once deliberations begin, but if an alternate replaces a juror mid-deliberation, the judge must instruct the jury to restart its discussions from the beginning.6Office of the Law Revision Counsel. Federal Rules of Criminal Procedure Rule 24 – Trial Jurors
Opening Statements
Once the jury is sworn in, each side gives an opening statement. These are not evidence. The party with the burden of proof — the prosecution in a criminal case, the plaintiff in a civil one — goes first and previews the story it plans to tell. The defense follows with its own preview, pointing at the facts it expects will weaken the other side’s theory. Attorneys are limited to describing what the evidence will show; they cannot argue why it entitles them to win. Even so, openings shape how jurors process everything that follows, and a clear one gives the jury a framework for the evidence.
Presenting the Evidence
The core of the trial is the presentation of evidence. The prosecution or plaintiff goes first with its case-in-chief, introducing physical exhibits, documents, photographs, and witnesses. When that side rests, the defense presents its case using the same tools.
Direct and Cross-Examination
Witness testimony is the most common form of evidence. On direct examination, the attorney who called the witness asks open-ended questions to bring out the facts that support that side’s story — “What did you see?” or “What happened next?” Cross-examination follows, and this is where testimony gets tested. The opposing attorney can probe the witness’s memory, surface inconsistencies, and draw out facts the witness left unsaid. This exchange is one of the trial’s core safeguards; it lets the jury weigh how credible each witness really is.
Expert Witnesses and Lay Witnesses
Witnesses fall into two categories. A lay witness can testify only to things they personally observed and can offer only everyday opinions, like an estimate of a car’s speed.7Cornell Law School Legal Information Institute (LII). Federal Rules of Evidence Rule 701 – Opinion Testimony by Lay Witnesses An expert witness has specialized knowledge — a forensic accountant, a physician, an accident reconstruction engineer — and can offer opinions rooted in that expertise, interpreting evidence in ways an ordinary witness cannot.
Objections and Evidence Rules
Attorneys can object throughout the trial when they think the other side is breaking an evidence rule, and the judge rules on each objection on the spot, deciding what the jury may hear. One of the most frequent objections is hearsay: an out-of-court statement offered to prove that what it says is true. Hearsay is generally inadmissible because the person who made the original statement isn’t in court to be cross-examined.8Cornell Law School Legal Information Institute (LII). Federal Rules of Evidence Rule 801 – Definitions That Apply to This Article, Exclusions from Hearsay Established exceptions cover business records, excited utterances, and statements made for medical treatment, among others, but the default rule keeps unreliable secondhand accounts out of the jury’s hands.
Rebuttal Evidence
After the defense rests, the prosecution or plaintiff gets a narrow chance to present rebuttal evidence. This is not a second run at the original case; it exists to counter new points the defense introduced. Rebuttal might mean recalling a witness or introducing a document that directly contradicts defense testimony.
Motions to End the Case Early
Once a side has finished presenting, the other side can ask the judge to end the trial by ruling that no reasonable jury could find against them on the evidence given. In civil cases this is a motion for judgment as a matter of law.9Cornell Law School Legal Information Institute (LII). Federal Rules of Civil Procedure Rule 50 – Judgment as a Matter of Law in a Jury Trial The criminal analog is a motion for judgment of acquittal. Courts grant these sparingly because they are reluctant to take the case from the jury, but when the evidence falls short, the motion prevents deliberation on an empty record.
Closing Arguments and Jury Instructions
When the evidence is in, each side gives a closing argument. Now the attorneys can argue: tying testimony to the legal claims, explaining why the evidence supports their version, and pointing out where the other side came up short. In a federal criminal trial, the prosecution closes first, the defense responds, and the prosecution gets the final word in rebuttal — a right the prosecution forfeits if it waives its initial close, which is why that gamble is rarely taken.10Cornell Law School Legal Information Institute (LII). Federal Rules of Criminal Procedure Rule 29.1 – Closing Argument
Then the judge reads the jury its instructions: the legal rules the jury must apply. The instructions define the elements of each charge or claim, spell out relevant standards, and set the limits on what the jury may consider. The jury doesn’t get to decide what the law is; it decides only whether the facts satisfy it.
The Burden of Proof
The most consequential piece of every instruction is the burden of proof, and it varies with the type of case. In a criminal trial, the government must prove guilt beyond a reasonable doubt — the highest standard the legal system uses. If a juror harbors a doubt grounded in reason about any element of the charge, they are to vote not guilty. In most civil trials the standard is preponderance of the evidence: more likely than not. Certain civil matters with severe consequences, like termination of parental rights, use a middle standard called clear and convincing evidence, requiring a firm belief that the claim is highly probable.
Deliberation and the Verdict
After instructions, the jurors move to a private room to deliberate. Their first task is picking a foreperson to lead the discussion, keep it organized, and communicate with the court. The foreperson has no extra voting power; the role is procedural.
Deliberation can take hours or weeks depending on the case. Jurors review the evidence, work through disagreements, and can send written questions to the judge for clarification on the instructions or to see a specific exhibit again. In high-profile cases with a real risk of outside influence, the judge may order the jury sequestered — housed in a hotel, cut off from media, and escorted by U.S. Marshals — to protect the deliberations.11United States Courts. How Courts Care for Jurors in High Profile Cases Sequestration is rare because of the burden on jurors, but it happens when threats or pervasive publicity leave no other option.
Unanimity and Hung Juries
Criminal verdicts must be unanimous. In Ramos v. Louisiana (2020), the Supreme Court confirmed that the Sixth Amendment requires a unanimous verdict to convict in every criminal trial, state or federal, ending non-unanimous convictions in the handful of states that had allowed them.12Supreme Court of the United States. Ramos v. Louisiana, No. 18-5924 Federal civil trials also require unanimity by default, though the parties can agree in advance to accept a non-unanimous result.2Cornell Law School Legal Information Institute (LII). Federal Rules of Civil Procedure Rule 48 – Number of Jurors, Verdict, Polling
When the jury cannot agree, the judge may send it back for more deliberation, sometimes with an instruction urging jurors to reconsider their positions while keeping their honest judgment. If the deadlock holds, the judge declares a hung jury and the trial ends in a mistrial. A hung-jury mistrial does not block the government from trying the case again; the Supreme Court has long held that double jeopardy does not attach when a jury fails to reach a verdict, because the trial was never completed.13Cornell Law School Legal Information Institute (LII). Reprosecution After Mistrial In practice, prosecutors weigh whether a retrial is worth pursuing and may negotiate a plea or drop charges.
What Happens After a Guilty Verdict
In criminal cases, the verdict does not produce a sentence on the spot. In federal court and most state courts, sentencing belongs to the judge. The judge sets a separate sentencing hearing weeks or months later, allowing time for a presentence investigation into the defendant’s background, criminal history, and the circumstances of the offense. Death penalty cases are the major exception, where the jury usually plays a direct role in whether a capital sentence is imposed.
If You’re Serving on the Jury
Federal jurors are paid $50 per day, and after 10 days the judge can raise the rate by up to $10 per day, capping it at $60, plus mileage to and from the courthouse.14Office of the Law Revision Counsel. 28 USC 1871 – Fees State pay varies and is often lower. Federal law makes it illegal for an employer to fire, threaten, or otherwise punish a permanent employee for serving on a federal jury, and a violating employer faces a civil penalty of up to $5,000 per violation along with possible reinstatement and back pay.15Office of the Law Revision Counsel. 28 USC 1875 – Protection of Jurors Employment Federal law does not require your employer to keep paying your regular wages during service. Some states do, and many large employers voluntarily cover the gap, but there is no national guarantee of paid jury leave, so check your employee handbook before your service date.