How Federal Grand Juries Work

By Jonathan Marks

Federal grand juries serve as a constitutional check on prosecutorial power, determining whether probable cause exists to issue an indictment. The Fifth Amendment requires grand jury indictment for all federal felonies.

Grand Jury Basics

• Composed of 16 to 23 citizens
• Requires a vote of at least 12 to return an indictment
• Proceedings are secret under Federal Rule of Criminal Procedure 6(e)
• Grand juries sit for up to 18 months, with possible 6-month extensions

What Happens During Proceedings

• Prosecutors present evidence and call witnesses
• Defendants typically cannot present evidence or cross-examine witnesses
• The standard is probable cause — much lower than beyond a reasonable doubt
• Grand juries have broad subpoena power for documents and testimony

Subpoena Compliance and Privileges

Witnesses who receive grand jury subpoenas must comply unless they invoke a valid privilege:

Fifth Amendment Privilege

• Witnesses may refuse to answer questions that could incriminate them
• Immunity (transactional or use immunity) may be offered to compel testimony

Attorney-Client Privilege

• Communications between attorney and client are protected
• The crime-fraud exception may override this privilege

Defense Strategy

• Advise clients on their rights before grand jury appearances
• Negotiate with prosecutors regarding scope of testimony
• Consider proffer agreements as alternatives to grand jury testimony
• Monitor for prosecutorial misconduct or irregularities
• Prepare for potential indictment and arraignment

Grand jury proceedings are a critical stage where early defense involvement can significantly impact case outcomes.