Final answer:
A sealed indictment is used in a federal criminal trial to keep the indictment secret until the defendant is in custody or released pending trial, to protect the defendant's right to a fair trial or prevent potential harm.
Step-by-step explanation:
The correct answer is 1) Sealed indictment.
In a federal criminal trial, when an indictment is returned to a magistrate judge, they may direct that the indictment be kept secret until the defendant is in custody or released pending the trial. This is called a sealed indictment. It is done to protect the defendant's right to a fair trial or to prevent potential harm, such as witness retaliation or disclosure of classified information.
For example, if a public trial would undermine the defendant's right to a fair trial, the trial can be held behind closed doors. However, this is done in only certain, narrow circumstances. The sealed indictment helps ensure the integrity of the trial process.