A judge in a criminal case may feel that it is appropriate to combine the cases of multiple defendants when their charges involve the same set of circumstances. This can help a judge streamline their calendar and resolve a case more efficiently. They will not need to go through the jury selection process multiple times, and witnesses will need to testify only once. Combining trials (also known as joinder) is only acceptable if it does not violate a defendant’s right to a fair trial. Sometimes one or more co-defendants will argue that a joint trial needs to be severed. This is especially likely if each co-defendant is arguing that the other co-defendant was solely responsible for the crime, or if each co-defendant is attacking the credibility of the other co-defendant’s version of events.
When to Join Trials
The main situation in which joining trials makes sense is when two or more defendants have been charged based on the same facts. They do not all need to have been charged with the same crime, although usually they are facing the same charge or some of the same charges. A judge should not join the trials of defendants who are charged with the same crime if their cases do not arise from the same facts. Every defendant who is charged with burglary in a jurisdiction, for example, should not stand trial together for that reason.
Joint Trials: Factors in Favor
Each defendant is charged based on the same or similar evidence
Each defendant allegedly participated in the same acts or transactions
The alleged crime involves a common scheme, conspiracy, or enterprise
Proof of one charge requires proof of another (e.g., one defendant is charged with theft, while the other is charged with the sale of stolen goods)
Judges have considerable discretion in determining whether a joint trial is appropriate, since there is no specific law or provision of the Constitution that covers them. Some factors to consider include whether the defendants were involved in the same set of events and whether the prosecution will be presenting the same evidence against them. It may be appropriate to try several defendants related to a drug distribution ring together, for example, even if some of them are being charged with drug manufacturing and others are being charged with drug trafficking. In some situations, a judge may join trials that are based on different charges if the prosecution would need to prove one charge to prove the others.
A joint trial often arises in cases involving conspiracy or sophisticated, organized criminal enterprises. It might be appropriate in a white collar crime case when multiple executives are being charged with fraud.
When to Sever Trials
A defendant generally does not have a right to a separate trial upon request, except in some narrow situations such as death penalty cases. However, a defendant can ask a judge to sever a joint trial if proceeding jointly would jeopardize their right to a fair trial. Sometimes the prosecution will submit certain evidence against only one defendant, which is not relevant to the other defendant. If this evidence would be prejudicial to the other defendant because it would inflame the emotions of the jury, a judge may decide to sever the trial.
Joint Trials: Factors in Opposition
Evidence against one defendant may prejudice another
Evidence is only admissible against one defendant and not the other
One defendant’s defense relies on disputing the other’s story of the case
Federal and state rules of evidence are extremely nuanced. A situation might arise in which evidence is admissible against one defendant but not the other. Instead of severing the trial, a judge might explore the possibility of less drastic solutions, such as jury instructions limiting the use of the evidence. Telling the jury to consider certain evidence with regard to only one defendant may not effectively protect the other defendant’s right to a fair trial, though. The opacity surrounding jury deliberations makes it hard to ensure that the jury will follow such complex instructions.