Final answer:
A Grand Jury hearing is typically limited to the presence of prosecutors, grand jurors, and witnesses during their testimony; defendants and defense attorneys are not present during deliberations.
Step-by-step explanation:
During a Grand Jury hearing, the presence of individuals is very limited to ensure the confidentiality and impartiality of proceedings. Typically, the individuals who can be present are the prosecutors, the grand jurors, and the witnesses while they are testifying. Unlike a typical jury trial, the defendant and their defense attorney do not have the right to be present during the grand jury's deliberations.
However, the Rules of Criminal Procedure for federal courts do permit a witness to have an attorney present in the building, but not directly in the grand jury room while they are testifying. The grand jury's proceedings are secret, and even after the hearing, jurors are generally prohibited from disclosing what happened to ensure the protection of the defendant's reputation if no indictment is issued.