A criminal trial has four main parts: jury selection, opening statements, the presentation of evidence, and closing arguments followed by jury deliberation and the verdict. Each of the four parts of a criminal trial has its own rules, and what happens in one stage shapes what’s possible in the next. The Sixth Amendment guarantees anyone accused of a serious crime a public trial before an impartial jury, which is why the process begins with picking that jury.
Part 1: Jury Selection
Before any evidence is heard, the court has to seat a fair jury. The selection process is called voir dire. The judge and the attorneys question a pool of potential jurors to screen out anyone who can’t be impartial. Questions cover things like whether a juror knows any of the parties, has prior knowledge of the case, or holds beliefs that would prevent a fair evaluation of the evidence.
Each side can remove jurors in two ways. A challenge for cause targets a specific, identifiable reason a juror shouldn’t serve, such as a personal relationship with the defendant or an admitted bias. There’s no limit on these, as long as the judge agrees the reason is valid. A peremptory challenge lets an attorney strike a juror without explaining why, and federal rules cap the number allowed based on the severity of the charge.1Legal Information Institute. Federal Rules of Criminal Procedure Rule 24 – Trial Jurors
Peremptory challenges come with one major limit. The Supreme Court held in Batson v. Kentucky that using them to strike jurors because of race violates the Equal Protection Clause.2Justia. Batson v. Kentucky, 476 U.S. 79 (1986) J.E.B. v. Alabama extended that protection to gender.3Justia. J. E. B. v. Alabama ex rel. T. B., 511 U.S. 127 (1994) If the other side suspects a discriminatory motive, they can raise a Batson challenge and force the striking attorney to offer a race- or gender-neutral explanation.
In longer trials, the court also seats alternate jurors who watch the proceedings alongside the regular panel and step in if a juror becomes sick, has an emergency, or is disqualified. Federal courts can seat up to six alternates, chosen through the same voir dire process.1Legal Information Institute. Federal Rules of Criminal Procedure Rule 24 – Trial Jurors If an alternate replaces a juror after deliberations have begun, the judge instructs the jury to start their discussions over.
Not every criminal trial uses a jury. A defendant can waive that right and let the judge alone decide guilt, which is called a bench trial. In federal court, the defendant must waive the jury in writing, the prosecution must consent, and the court must approve.4Office of the Law Revision Counsel. Federal Rules of Criminal Procedure Rule 23 – Jury or Nonjury Trial Defendants sometimes choose a bench trial when the facts are highly technical or when they believe a judge will be less swayed by emotional evidence.
Part 2: Opening Statements
Once the jury is seated, each side gives an opening statement. These are previews. Each attorney lays out what they expect the evidence to show and gives the jury a framework for understanding the testimony and exhibits that will follow. Opening statements aren’t evidence, and jurors are instructed not to treat them as proof of anything.
The prosecution goes first because it carries the burden of proving guilt. The prosecutor walks the jury through the key facts they plan to establish and the witnesses they intend to call. The defense attorney follows, highlighting weaknesses in the prosecution’s theory or previewing an alternative explanation. In some jurisdictions, the defense can delay its opening statement until after the prosecution has finished presenting all of its evidence, a tactical choice that lets the defense tailor its preview to what the jury has actually heard.
Part 3: Presenting Evidence
The evidence phase is where the case is built or dismantled. It is usually the longest part of a trial, and the rules governing what the jury can hear are some of the most complex in the legal system.
Direct Examination and Cross-Examination
The prosecution presents its case first, calling witnesses and introducing physical evidence, documents, and recordings. When the prosecution questions its own witnesses, that’s direct examination. The questions tend to be open-ended, letting the witness describe events in their own words. Leading questions that suggest the answer are generally not allowed on direct.5Legal Information Institute. Federal Rules of Evidence Rule 611 – Mode and Order of Examining Witnesses and Presenting Evidence
After each prosecution witness testifies, the defense gets to cross-examine. Cross-examination is where leading questions are expected, because the whole point is to test the account. A defense attorney might challenge the witness’s memory, point out inconsistencies, or suggest the witness has a reason to shade the truth. Cross-examination is limited in scope to what was covered during direct and matters affecting credibility.5Legal Information Institute. Federal Rules of Evidence Rule 611 – Mode and Order of Examining Witnesses and Presenting Evidence
After the prosecution rests, the defense can present its own witnesses and evidence using the same format. The defense is never required to put on a case at all. The Fifth Amendment protects defendants from being forced to testify against themselves, so a defendant who never takes the stand is exercising a constitutional right.6Library of Congress. Constitution of the United States – Amendment 5 Judges instruct juries not to draw any negative conclusions from a defendant’s silence.
Objections and the Hearsay Rule
Throughout testimony, attorneys can object to questions or evidence they believe violate the rules. The judge rules immediately. Sustaining the objection keeps the evidence out; overruling it lets the jury hear it. Common objections involve relevance, improper questioning techniques, or attempts to introduce unreliable evidence.
One of the most frequently invoked evidence rules involves hearsay — an out-of-court statement a party tries to use at trial to prove that what the statement says is true. If a witness testifies “my neighbor told me he saw the defendant at the scene,” that’s hearsay, because the neighbor isn’t on the stand and can’t be cross-examined. Hearsay is generally not admissible, but the exceptions are numerous. Statements made in the heat of a startling event, statements made to a doctor for purposes of medical treatment, and descriptions of something a person was observing at the very moment they spoke can all come in despite being hearsay.7Legal Information Institute. Federal Rules of Evidence Rule 803 – Exceptions to the Rule Against Hearsay Business records and public records fall under their own exceptions.
Expert Witnesses
Some evidence requires specialized knowledge an ordinary witness can’t provide. Expert witnesses offer opinions on topics like DNA analysis, accident reconstruction, financial fraud, or mental health. Unlike regular witnesses, experts are allowed to state opinions and draw conclusions from the evidence. Before an expert can testify, the judge acts as a gatekeeper, evaluating whether the expert’s methods are reliable and whether the testimony will actually help the jury. Federal courts consider factors like whether the methodology has been tested, whether it has been peer-reviewed, its known error rate, and whether it is generally accepted in the field.
Motion for Judgment of Acquittal
After the prosecution rests, the defense can ask the judge to end the trial by filing a motion for judgment of acquittal. The argument is that even viewing the prosecution’s evidence in the most favorable light, no reasonable jury could find the defendant guilty. If the judge agrees, the case is over. If the judge denies the motion, the trial continues, and the defense can renew it after all evidence is presented or even after a guilty verdict.8Justia. Federal Rules of Criminal Procedure Rule 29 – Motion for a Judgment of Acquittal Judges grant these motions sparingly, but defense attorneys file them routinely to preserve the issue for appeal.
Part 4: Closing Arguments and the Verdict
After both sides have finished presenting evidence, the trial enters its final phase. Closing arguments are each attorney’s last chance to speak directly to the jury, and they carry real weight because everything the jury has seen gets filtered through these final narratives.
Closing Arguments
The prosecution argues first, walking the jury through the evidence and explaining how it satisfies every element of the charged crime. The defense follows, poking holes in that case, emphasizing reasonable doubt, and offering alternative interpretations. Because the prosecution carries the burden of proof, federal rules give the prosecution a final rebuttal after the defense’s closing.9Legal Information Institute. Federal Rules of Criminal Procedure Rule 29.1 – Closing Argument That rebuttal is limited to responding to points the defense raised, but it is a significant tactical advantage: the prosecution gets both the first and the last word.
Jury Instructions
Before the jury begins deliberating, the judge reads a set of instructions explaining the relevant law. These define the specific crime charged, list the elements the prosecution must prove, and explain the “beyond a reasonable doubt” standard. Attorneys on both sides typically submit proposed instructions and fight hard over the exact wording, because a single phrase can tilt how the jury understands its job. Errors in jury instructions are one of the most common grounds for appeal.
Deliberation and the Verdict
The jury then retreats to a private room to deliberate. No one else is present. Jurors are free to discuss the evidence, review exhibits, and request read-backs of testimony. A guilty verdict must be unanimous in both federal and state criminal trials for serious offenses. The Supreme Court confirmed the unanimity requirement applies to the states in Ramos v. Louisiana, holding that the Sixth Amendment’s jury trial guarantee demands it.10Supreme Court of the United States. Ramos v. Louisiana, 590 U.S. ___ (2020)
If the jury reaches a unanimous guilty verdict, the defendant is convicted. If the jury unanimously finds the defendant not guilty, the acquittal is final and the defendant cannot be retried for the same offense. When jurors cannot reach agreement after extended deliberation, the result is a hung jury. The judge declares a mistrial, and the prosecution must decide whether to try the case again with a new jury. A hung jury does not count as an acquittal, so retrial is permitted.
What Comes Next
The four parts cover the trial itself, but the legal process often continues. A guilty verdict leads to a sentencing hearing, where the judge weighs aggravating and mitigating factors, hears from victims, and consults a presentence investigation report prepared by a probation officer.11United States Courts. Presentence Investigations The defense can also file post-trial motions, including a renewed motion for judgment of acquittal within 14 days of the verdict, and can appeal the conviction to a higher court.12Legal Information Institute. Federal Rules of Criminal Procedure Rule 29 – Motion for a Judgment of Acquittal An appeal is not a new trial. The appellate court reviews the trial record for legal errors such as improper admission of evidence, flawed jury instructions, or constitutional violations, and can affirm the conviction, reverse it, or send the case back for further proceedings.