A federal criminal complaint is the short, sworn charge that lets a judge issue an arrest warrant. The affidavit behind it is an agent's sworn account of why there is probable cause. Read it from paragraph one, find where the investigation's story begins, and ask what came before that. The affidavit is written to justify an arrest, not to tell you how the case started. That first step is the question we track.
Key takeaways
- Under Fed. R. Crim. P. 3, a complaint is a written statement of the essential facts of the offense, made under oath before a magistrate judge.
- Under Fed. R. Crim. P. 4, if the complaint or attached affidavits establish probable cause, the judge must issue an arrest warrant, or a summons if the government asks.
- Complaints are often linked from U.S. Attorney's Office press releases. On PACER, documents cost $0.10 a page, capped at $3, and quarterly bills of $30 or less are waived.
- Affidavits routinely say they don't contain everything the government knows. That's standard. It also means the real starting point can sit outside the document.
- At a preliminary hearing, a defendant can't object that evidence was unlawfully acquired (Fed. R. Crim. P. 5.1). Origin fights happen later, in discovery and motions.
01Where to find a complaint
Start with the prosecutor's office. Each U.S. Attorney's Office posts press releases on justice.gov, and releases about new arrests often link the charging papers. In the Mall of America case, the District of Minnesota's press release linked directly to the complaint and affidavit.
If there's no link, go to the court. PACER is the federal judiciary's paid records system. Its fee page sets the price at $0.10 per page, with no single document costing more than $3. Search results, some reports and transcripts aren't capped. If your charges for a quarter total $30 or less, they're waived. Court opinions are free, and viewing case information at any federal courthouse is free.
Before paying, check CourtListener. Its archive is fed by RECAP, a free browser extension from Free Law Project: when users buy documents on PACER, the extension adds them to a public archive, and documents other users already bought show up free.
Docket numbers. The Mall of America complaint carries No. 26-mj-760 (ECW); the "mj" marks a magistrate-judge matter. Search by docket number as well as by name, and copy it exactly when you cite or send it.
02The anatomy: complaint, affidavit, warrant
A complaint package usually has three parts. Each answers a different question.
| Part | What it is | Read it for |
|---|---|---|
| Complaint | A one- or two-page form naming the defendant and the statute charged, sworn before a magistrate judge (Rule 3). | The exact charge, the date range alleged and the district. |
| Affidavit | The agent's sworn narrative, in numbered paragraphs, attached to support probable cause. | Who the agent is, what's alleged and, most of all, where the story begins. |
| Warrant or summons | Issued by the judge if probable cause is shown (Rule 4). | The judge's name and the date; a warrant must describe the offense and be signed by a judge. |
Probable cause here means enough facts to believe an offense was committed and that this defendant committed it. It's a low bar compared with proof beyond a reasonable doubt. A complaint is an accusation. The person named is presumed innocent.
03The affiant and the boilerplate
The first paragraphs are about the affiant, the agent swearing to the facts: years with the FBI, training, prior cases. It's background, offered to show the agent's judgment deserves weight.
Then comes a line that almost every affidavit includes. In the Mall of America affidavit, it says the document "does not set forth all of my or the government's knowledge about the matter" (¶4, as quoted in our case file).
Read that line carefully. It's not a confession. The usual reason is practical: an affidavit only has to establish probable cause, not lay out the whole investigation. But it also means the true starting point of an investigation can sit entirely outside the only document the public gets to read.
It doesn't say what was left out, or why. Nothing in that sentence, by itself, is evidence that anything was hidden. It's the reason to look at what the narrative does and doesn't explain.
04Numbered paragraphs, footnotes and the CHS
Affidavits are written in numbered paragraphs so they can be cited precisely. Cite them that way yourself. "¶12" is checkable. "The FBI said" isn't.
Watch for CHS, the FBI's abbreviation for a confidential human source, an informant. Affidavits usually give sources a label ("CHS1") rather than a name, and put details about them in footnotes: how long they've worked with the Bureau, whether they're paid, whether their past information proved reliable.
In the Mall of America affidavit, footnote 1 says CHS1 has worked with the FBI since 2017 and is "motivated by patriotism and monetary compensation" (as quoted in our case file). That footnote tells you the first documented contact was with a paid source. Whether a defendant can learn more about that source is a separate fight; see Can a Defendant Learn Who the Confidential Informant Is?
Our rule: never speculate about who a source is. The label is all the public record gives, and it's all we use.
05Finding the first step
Find the paragraph where the investigation's narrative begins. Then ask what comes before it.
Worked example. The Mall of America affidavit's story opens with the FBI's statement that it had been conducting a national security investigation "since December 2024" (¶11). The next paragraph says that in or about December 2024, CHS1 began exchanging messages with the defendant (¶12). There is no tip, no platform referral and no earlier case described as the trigger. The defendant was 16 or 17 at the time. That is the gap our case file is built around.
Compare Case File 002. There, the FBI affidavit cites tips on specific dates. A dated, sourced origin doesn't end the inquiry, but it gives the defense something concrete to test.
- Does the narrative say what first brought the person to the government's attention, with a date?
- Does it say who contacted whom first?
- Does any legal process (a subpoena, a records request) appear before the first described investigative step?
- Is any step described in the passive voice, with no agency or source named ("information was obtained")?
- Does the affidavit mention FISA, classified information or another agency's involvement, or is it silent?
06What happens after the complaint
The complaint is the beginning of the paper record, not the end. Under Fed. R. Crim. P. 5.1, a magistrate judge must hold a preliminary hearing unless the defendant waives it, is indicted, or the government files an information (a charge filed by the prosecutor without a grand jury). It must happen within 14 days of the initial appearance if the defendant is in custody, 21 if not.
At that hearing, the defendant can cross-examine witnesses and introduce evidence, but can't object that evidence was unlawfully acquired. If the judge finds no probable cause, the complaint is dismissed, though the government can charge the same offense later.
Separately, the Speedy Trial Act generally requires an indictment or information within 30 days of arrest, subject to exclusions (18 U.S.C. § 3161).
That's why origin questions are fought through other tools: discovery demands under Brady, Rule 16 and Franks, and the government's duty to give notice of FISA-derived evidence.
07A checklist of origin gaps, and how we grade them
When we read an affidavit for a case file, we run this checklist. Any one item is a question, not a conclusion.
- The investigation's opening date is given with no stated reason.
- The first documented contact is with a paid or long-serving source.
- Records were obtained (phone, platform, financial) before any described lead pointed to them.
- The narrative jumps from "we learned" to "we confirmed" without the learning.
- A traffic stop, "anonymous tip" or chance encounter starts the story.
- No mention of FISA or classified material, in a national security case. That may mean there was nothing to disclose.
Then we grade the file on our public scale (How We Grade):
| Grade | What it means |
|---|---|
| Watching | The public record documents how the case began. We track filings for anything that changes that. |
| Open Questions | The record leaves a gap in how the investigation began, or the origin depends on sources the defense hasn't seen. |
| Notice Filed | The government has given notice of FISA-derived evidence or is litigating classified material under CIPA. |
| Confirmed | A court, the government or primary documents establish that the case's true origin was concealed. |
08FAQ
What is the difference between a complaint and an indictment?
A complaint is a written statement of the essential facts, made under oath before a magistrate judge. An indictment is a charge returned by a grand jury. Under Rule 5.1, an indictment makes the preliminary hearing unnecessary.
Why doesn't the FBI affidavit tell the whole story?
An affidavit only has to establish probable cause, and most say they do not set forth everything the government knows. That is standard, but it means the real starting point of an investigation may not appear in it.
How much does it cost to get a complaint on PACER?
PACER charges $0.10 per page, with most documents capped at $3. Charges of $30 or less in a quarter are waived, and viewing case information at a federal courthouse is free. Check CourtListener's RECAP archive first, where documents are free.
Does a criminal complaint mean the person is guilty?
No. A complaint is an accusation supported by probable cause, a far lower standard than proof beyond a reasonable doubt. Everyone charged is presumed innocent.
Can I figure out who the confidential source is from the affidavit?
Usually not, and we don't try. Affidavits refer to sources by labels like CHS1. Whether a defendant can learn a source's identity is decided by the court in discovery.
Found an affidavit with a gap at the start?
Send us the court and the docket number. We'll read it against the checklist above, and if it belongs on the record, we'll build a case file from public documents and grade it. If you are the person charged, talk to your own lawyer before sharing anything about your case with anyone, including us. Messages to us are not privileged.
09Sources
Every fact in this dispatch comes from the documents below. If you spot an error, tell us and we'll correct it on this page.
- Federal Rule of Criminal Procedure 3 (The Complaint), Cornell LII
- Federal Rule of Criminal Procedure 4 (Arrest Warrant or Summons on a Complaint), Cornell LII
- Federal Rule of Criminal Procedure 5.1 (Preliminary Hearing), Cornell LII
- 18 U.S.C. § 3161 (Speedy Trial Act), Cornell LII
- PACER, "PACER Pricing: How Fees Work"
- Free Law Project, RECAP
- CourtListener
- U.S. Attorney's Office, D. Minn., press release, Oct. 7, 2026
- Criminal complaint and FBI affidavit, United States v. Mohamud, No. 26-mj-760 (ECW), Oct. 2026
- FBI affidavit, United States v. Kramer, Mag. No. 26-1518 (W.D. Pa.), Sept. 13, 2026
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Public education, not legal advice. We are not attorneys. If you are facing charges, talk to your lawyer before sharing anything about your case with anyone, including us.