What is a Criminal Jury Trial?

My name is Anzac Jacobs, and I am a criminal defense attorney with the Law Offices of Bamieh & De Smeth. For more than 16 years, I have defended individuals facing criminal charges in Ventura and Santa Barbara Superior Courts, handling a wide range of cases, from traffic infractions and misdemeanor vandalism to serious felony offenses, including homicide.

The Constitutional Right to a Criminal Jury Trial in California

The right to a trial by an impartial jury is a cornerstone of the United States criminal justice system, guaranteed by both the Sixth Amendment to the United States Constitution and Article I, Section 16 of the California Constitution. In California courtrooms, the criminal jury trial unfolds as a highly structured, adversarial process designed to protect the liberties of the accused while allowing the state to enforce its penal laws.

A California criminal jury trial is a complex mechanism governed by the California Penal Code, the California Code of Civil Procedure, and established case law. Understanding this process requires examining its sequential stages: pretrial procedures, jury selection (voir dire), the presentation of evidence, jury instructions, closing arguments, and finally, deliberation and verdict. Each phase plays a vital role in balancing judicial efficiency with the constitutional mandate of due process.

Pretrial Procedures and Evidentiary Motions

Before a panel of citizens ever sets foot in a courtroom, a lengthy pretrial process shapes the boundaries of the trial. Following an arrest, a defendant is arraigned, charges are formally read, and pleas are entered. In felony cases, a preliminary hearing is conducted where a magistrate determines whether probable cause exists to bind the defendant over for trial.

A crucial mechanism preceding the trial itself is the litigation of motions in limine. These are pretrial motions argued before the trial judge to determine the admissibility of specific evidence, statements, or testimony. For instance, a defense attorney may file a motion to suppress evidence under Penal Code Section 1538.5, arguing it was obtained through an unlawful search and seizure. Alternatively, prosecutors might seek to admit evidence of prior bad acts under California Evidence Code Section 1101(b). The judge’s rulings on these motions establish the legal guardrails of the trial, ensuring the jury is not exposed to highly prejudicial or legally compromised information.

Jury Selection Through Voir Dire

Jury selection, or voir dire (meaning "to speak the truth"), is arguably the most critical phase of a criminal trial. In California, criminal juries traditionally consist of twelve citizens, though the parties can agree to a lesser number in misdemeanor cases. The process begins when a pool of prospective jurors, drawn from DMV records, voter registration lists, and state tax filings, is brought into the courtroom.

The primary objective of voir dire is to select twelve fair and impartial individuals, along with necessary alternates. Under California Code of Civil Procedure Section 223, the trial judge conducts an initial examination of the prospective jurors, after which counsel for both the prosecution and defense have the right to ask follow-up questions. Attorneys evaluate jurors for bias through two primary mechanisms:

1. Challenges for Cause: An attorney can request that a juror be excused if they demonstrate actual bias (an inability to be impartial) or implied bias (such as being related to a party in the case). There is no limit to the number of challenges for cause.
2. Peremptory Challenges: These allow attorneys to excuse a juror without giving a reason. The number of peremptory challenges allocated to each side depends on the severity of the offense. Under California law, for offenses punishable by death or life imprisonment, each side receives 20 peremptory challenges. For standard felonies, they generally receive 10, and for misdemeanors, the allocation drops to 6.

Crucially, peremptory challenges cannot be used to discriminate based on race, ethnicity, gender, or other protected characteristics. In California, if a party believes the opposition is using peremptory challenges discriminatorily, they can make a Batson/Wheeler motion. If the judge finds a prima facie case of discrimination, the opposing counsel must provide a race- or group-neutral explanation for the challenge.

Presenting Evidence and Examining Witnesses

Once the jury is sworn in, the trial transitions to its core adversarial phase: the presentation of evidence. The trial officially opens with opening statements. The prosecution, carrying the absolute burden of proof, goes first, followed by the defense (though the defense may choose to reserve its opening statement until after the prosecution rests). Opening statements are not arguments; rather, they serve as a road map, outlining what each side expects the evidence to show.

Because the defendant is presumed innocent until proven guilty, the prosecution must present its case-in-chief first. The state must prove every element of the charged crimes beyond a reasonable doubt, which is the highest standard of proof in the American legal system.

The presentation of evidence is strictly governed by the California Evidence Code and relies on two main types of proof: direct evidence (such as eyewitness testimony or video footage) and circumstantial evidence (indirect evidence that requires an inference to connect it to a conclusion).

How Witness Examination Works

The examination of witnesses follows a strict protocol:

• Direct Examination: The calling attorney questions their witness using open-ended questions to elicit their narrative.
• Cross-Examination: The opposing attorney questions the witness using leading questions. Cross-examination is a vital tool used to test the witness’s credibility, memory, perception, and potential bias.
• Redirect and Recross: The calling attorney may ask follow-up questions to rehabilitate a witness whose credibility was attacked during cross-examination, followed by a final opportunity for the opponent to question those specific points.

Once the prosecution rests its case, the defense has the opportunity to present its case-in-chief. However, because the burden of proof rests entirely on the state, the defense is not required to present any evidence or call any witnesses. Furthermore, under the Fifth Amendment, a criminal defendant has the absolute right to remain silent and choose not to testify. If the defendant exercises this right, the jury is explicitly instructed that they cannot use the defendant's silence as an inference of guilt.

Jury Instructions and the Applicable Law

After both sides rest, the trial judge must instruct the jury on the applicable law. In California Superior Courts, judges utilize the California Criminal Jury Instructions (CALCRIM). These standardized instructions translate complex legal statutes and appellate case law into plain, comprehensible language for lay jurors.

Jury instructions cover fundamental legal concepts, such as the definition of reasonable doubt, how to evaluate witness credibility, and the difference between direct and circumstantial evidence. Crucially, the judge also instructs the jury on the specific elements of the crimes charged. For example, in a first-degree murder trial, the judge will read CALCRIM instructions detailing what constitutes malice aforethought, premeditation, and deliberation. The jury's role is strictly that of a "finder of fact"; they must accept the law as given by the judge and apply those facts to the legal framework provided.

Closing Arguments From the Prosecution and Defense

With the evidence closed and the legal parameters set, attorneys deliver their closing arguments. This is the stage where advocacy peaks. Unlike opening statements, closing arguments are highly persuasive and analytical. Attorneys synthesize the testimonies, physical evidence, and jury instructions to construct a cohesive narrative that supports their desired outcome.

The prosecution speaks first, utilizing the opportunity to demonstrate how the evidence satisfies every element of the crime beyond a reasonable doubt. The defense follows, pointing out flaws in the investigation, highlighting inconsistencies in witness statements, and arguing that the prosecution has failed to overcome the high hurdle of reasonable doubt. Because the prosecution carries the ultimate burden of proof, they are granted the unique advantage of a final rebuttal argument, allowing them the last word before the jury begins deliberations.

Jury Deliberations and the Unanimous Verdict

Following closing arguments, the alternate jurors are separated, and the twelve primary jurors are escorted to a private deliberation room by a court bailiff. The jury’s first order of business is to select a foreperson to oversee the discussions and act as the spokesperson for the panel.

During deliberations, jurors review the admitted evidence and discuss the case. If they have questions regarding the law or wish to have specific portions of witness testimony read back to them, they submit a written note to the judge, and the parties reassemble in open court to address the request.

In California criminal trials, a verdict must be unanimous—whether it is a conviction or an acquittal. This requirement applies to both felonies and misdemeanors.

If all twelve jurors agree that the prosecution proved the defendant's guilt beyond a reasonable doubt, they return a verdict of guilty. If they agree the state failed to meet this standard, they return a verdict of not guilty, resulting in an acquittal. Due to constitutional protections against double jeopardy, an acquittal immediately ends the state’s prosecution for that specific crime, and the defendant is released.

What Happens When a Jury Cannot Reach a Verdict?

If the jurors reach an absolute impasse and cannot achieve a unanimous consensus after extensive deliberation, the foreperson informs the judge. If the judge concludes that further deliberations will not yield a verdict, a mistrial is declared due to a "hung jury." In this event, the case is not dismissed; rather, the prosecution retains the discretion to retry the defendant before a brand-new jury panel, negotiate a plea bargain, or dismiss the charges entirely.

Protecting Defendants’ Rights Throughout a California Criminal Trial

Criminal jury trials in California Superior Courts reflect a deeply rooted constitutional commitment to democracy and individual liberty. By placing the ultimate power of judgment in the hands of twelve ordinary citizens, the system creates a vital buffer between the coercive power of the state and the individual citizen. From the strategic positioning of voir dire to the strict evidentiary boundaries of the case-in-chief, every step of a California criminal trial is designed to safeguard fairness. While the process can be slow, adversarial, and occasionally inconclusive, it remains an indispensable framework for pursuing justice and upholding the rule of law in California.