Criminal procedure
Criminal Complaint
A criminal complaint is a sworn statement of facts, usually by a federal agent, that establishes probable cause and allows an arrest before any indictment.
It is the fast start. When an investigation needs to move now, an agent signs an affidavit, a magistrate judge finds probable cause, and an arrest warrant issues. The complaint carries the case only temporarily.
The government must then indict within thirty days of arrest, so a complaint almost always leads to an indictment or a resolution within weeks. Complaint affidavits are often the most detailed public account of the alleged conduct in the whole case.
Because complaints are written to establish probable cause, they often narrate the investigation in unusual detail. Search results, surveillance, cooperating witness accounts, and message excerpts appear in them long before any trial exhibit does.
How it appears on a docket
COMPLAINT and AFFIDAVIT of Special Agent T. Ruiz as to Daniel R. Vance charging wire fraud. Arrest warrant issued 1/9/2026.
Governing rule
Fed. R. Crim. P. 3, 4; 18 U.S.C. Sec. 3161(b)
Related terms
- Arrest Warrant — An arrest warrant is a judge's written authorization for law enforcement to take a named person into custody.
- Initial Appearance — An initial appearance is the first court date after an arrest, where the defendant is told the charges and the court addresses a lawyer and release.
More on criminal procedure
See this term in a real case
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