Explainer

When Can a Judge Declare a Mistrial?

Whenever jurors drink beer with lunch.

The defendants at the Tyco trial—two former executives facing a 32-count indictment that includes grand larceny and falsifying business records—requested a mistrial twice this week, once on Monday, and once yesterday. *  After one juror allegedly flashed an “OK” sign to the defense, lawyers for the two defendants argued that the publicity surrounding the incident—two media outlets had published the juror’s name—could unduly influence her decision. New York State Supreme Court Judge Michael Obus rejected the defense’s Monday request, ruling that a mistrial would be “inappropriate,” and is currently considering the second one. What are the possible grounds for mistrials?

Trial judges have ultimate discretion, and anything that might impede a jury’s ability to remain impartial or prevent it from reaching a unanimous decision is grounds for a mistrial. One of the earliest articulations of the standard comes from an opinion written by the 19th-century Supreme Court Justice Joseph Story, who wrote that judges should declare a mistrial whenever “there is a manifest necessity for the act, or the ends of public justice would otherwise be defeated.”

The “manifest necessity” standard has proven amorphous. There is a plethora of circumstances that could warrant a mistrial, including procedural error; misconduct; the illness or injury of a lawyer, judge, or juror that prevents him or her from continuing; or an unexpected event, such as an outburst in the courtroom, that might unfairly influence the jury. Mistrials can occur for more idiosyncratic reasons as well: A West Virginia judge recently declared one because a juror drank beer during the lunch break.

A “hung jury”—when a jury is deadlocked with no hope of coming to an agreement—is also grounds for a mistrial. That was the basis for the mistrial declared in the recent high-profile prosecution of former Credit Suisse First Boston investment banker Frank Quattrone. (Interestingly, Quattrone’s jury operated with 11 people, one short of the standard 12. One juror was excused during deliberations after a member of her family suffered a heart attack. When jurors need to be excused for such emergencies, federal trial rules allow for juries with fewer than 12 jurors to continue deliberations. Jury deliberation with fewer than 11 jurors requires the consent of both lawyers in the case, otherwise the judge must declare a mistrial.)

Mistrials typically benefit defendants, and defense counsel therefore request them more frequently than prosecutors. Because the prosecution must prove a case beyond a reasonable doubt, situations presented by the passage of time—fading memories, disappearing witnesses, changing testimonies—can be more of a hindrance to the prosecution than to the defense. Moreover, in some instances, a defendant cannot be tried again after a mistrial. The double-jeopardy clause of the Constitution prohibits the state from trying someone for the same crime twice. This clause, which is simply worded yet extremely complicated when applied, can preclude the state from retrying a defendant when a judge has declared a mistrial for reasons that do not rise to the level of “manifest necessity” and the defendant did not request or consent to the mistrial.

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Explainer thanks Richard UvillerofColumbia School of Law and Stephen Schulhofer of NYU School of Law.

Correction, April 5, 2004: The executives in the Tyco case faced a 32-count indictment that included grand larceny and falsifying business records, not 32 counts of enterprise corruption, as was stated in the original version of the story. Return to the corrected sentence.