Motion to suppress evidence in federal court

A motion to suppress asks a federal judge to bar the government from using certain evidence because it was obtained in violation of the defendant's constitutional rights, most often through an unlawful search (Fourth Amendment) or an improper interrogation (Fifth Amendment). In federal court the motion generally must be made before trial (Fed. R. Crim. P. 12(b)(3)(C)).

What is a motion to suppress?

It is a pretrial motion asking the court to exclude evidence. A defendant files it in the court where the trial will take place (Fed. R. Crim. P. 41(h)). Common targets of a suppression motion are physical evidence and data from a search, and statements made to agents. The judge often holds an evidentiary hearing, where agents and other witnesses testify, and must state the essential findings on the record when the motion turns on disputed facts (Fed. R. Crim. P. 12(d)).

Whether a motion has a basis depends on the warrant, the affidavit behind it, how the search or interview happened and what discovery shows. A motion to suppress is a request, not a finding that anything was unlawful.

When do you file a motion to suppress in federal court?

In practice, the deadline is usually set in a scheduling order soon after arraignment, so the defense needs to review discovery early.

What is the exclusionary rule, and what are its limits?

The Fourth Amendment protects against unreasonable searches and seizures and requires warrants to rest on probable cause and to particularly describe the place to be searched and the things to be seized. The exclusionary rule is the remedy courts created: evidence obtained through an unconstitutional search may be kept out of the government’s case. It has important limits:

• Good faith. In United States v. Leon, 468 U.S. 897 (1984), the Supreme Court held that evidence is generally not suppressed when officers relied in objective good faith on a warrant from a neutral judge that later turns out to be invalid. Suppression can still be appropriate if the judge was misled by information the affiant knew was false or recklessly disregarded the truth; if the judge wholly abandoned the judicial role; if the affidavit was so lacking in signs of probable cause that belief in it was entirely unreasonable; or if the warrant was so plainly deficient, for example in describing what to search or seize, that officers could not reasonably presume it valid.
• Standing. Fourth Amendment rights are personal and “may not be vicariously asserted.” A defendant can challenge a search only if it violated the defendant’s own reasonable expectation of privacy (Rakas v. Illinois, 439 U.S. 128 (1978), a Fourth Amendment ruling that applies in federal cases).

What is a Franks hearing?

A Franks hearing tests whether the sworn affidavit behind a warrant was truthful. Under Franks v. Delaware, 438 U.S. 154 (1978), the defendant gets a hearing only after making a substantial preliminary showing that the affiant included a false statement knowingly and intentionally, or with reckless disregard for the truth, and that the statement was necessary to the finding of probable cause. If the defendant then proves this by a preponderance of the evidence, and what is left of the affidavit does not establish probable cause, the warrant is voided and its fruits are excluded.

Can statements to agents be suppressed?

Sometimes. Under Miranda v. Arizona, 384 U.S. 436 (1966), the government may not use statements from custodial interrogation unless the person was first warned of the right to remain silent, that anything said can be used against them, and of the right to a lawyer, appointed if they can’t afford one, and then knowingly and intelligently waived those rights. If the person asks for a lawyer or says they want to remain silent, questioning must stop. The warnings apply only to questioning in custody, so whether a person was “in custody” is often the key issue.

What about phones and location data?

• Phones. In Riley v. California, 573 U.S. 373 (2014), all nine Justices agreed that police generally may not search the digital data on a phone seized from an arrested person without a warrant. Its answer to what police must do was simple: “get a warrant.” Emergencies (exigent circumstances) can still justify a warrantless search in a particular case. Riley is a Fourth Amendment ruling and applies in federal cases; it was decided together with a federal case, United States v. Wurie.
• Cell-site records. In Carpenter v. United States, 585 U.S. 296 (2018), the Court held 5–4 that the government’s acquisition of historical cell-site location information from a wireless carrier is a search, that accessing even seven days of those records counts, and that the government generally needs a warrant to get them. The Court called its decision “a narrow one” and did not decide questions such as real-time location data or “tower dumps.”

What is a geofence warrant?

A geofence warrant asks a technology company for data about the cell phones located inside a drawn area, the “geofence”, near the time of a crime. Police usually use one when they know where and when a crime happened but don’t have a suspect. In the Chatrie case, the warrant to Google covered a 150-meter radius around a credit union that had been robbed, and it worked in three steps:

1. Google produced anonymized location data for every phone inside the geofence from 30 minutes before to 30 minutes after the robbery.
2. Officers narrowed the list, and Google gave more anonymized data for those phones, inside and outside the geofence, over a two-hour period.
3. Officers narrowed it again, and Google turned over names and phone numbers for the users on the final list.

Did the Supreme Court rule on geofence warrants?

In part. In Chatrie v. United States, 609 U.S. 605 (2026), decided June 29, 2026, the Court vacated the Fourth Circuit’s judgment and sent the case back. The judgment was 6–3. Justice Kagan wrote the opinion of the Court for five Justices (Chief Justice Roberts and Justices Sotomayor, Kavanaugh and Jackson). Justice Gorsuch agreed with the result on different reasoning. Justices Alito, Thomas and Barrett dissented: Justices Thomas and Barrett each joined parts of Justice Alito’s dissent, and Justice Barrett also wrote a separate dissent.

What the Court decided. When police obtained Chatrie’s Location History data from Google, that was a Fourth Amendment search, because a person has a reasonable expectation of privacy in their cell-phone location information. Applying Carpenter, the Court held that the third-party doctrine does not remove that protection just because a user turned on Location History, and it rejected the argument that a short window of data doesn’t count.

What it left open.

• Whether the warrant was valid. Finding a search does not decide whether the search was unreasonable. The Court left it to the Fourth Circuit to decide whether, at each step, the warrant met the Fourth Amendment’s probable-cause and particularity requirements.
• Good faith. The Court agreed to decide only whether the police violated the Fourth Amendment. It did not decide whether the good-faith exception still allows the evidence; the Fourth Circuit may consider that anew.
• Emergencies. The Court said its decision does not call into doubt a warrantless geofence search in exigent circumstances.

How lower courts had split. Before Chatrie, the Fourth Circuit panel held that obtaining two hours of Location History was not a search, a view the Supreme Court has now rejected. The Fifth Circuit, in United States v. Smith, 110 F.4th 817 (5th Cir. 2024), held that geofence warrants, at least as described in that case, are “modern-day general warrants” the Fourth Amendment forbids, though it still upheld the convictions under the good-faith exception. That holding binds courts in the Fifth Circuit only, and the Supreme Court has not addressed it. Our news post on Chatrie has more on the decision.

For a person charged in a case built on a geofence warrant, these questions are argued case by case, based on the warrant’s own terms and the circuit’s law. The decision does not mean any particular geofence evidence will be suppressed.

Where does a motion to suppress fit in a federal case?

Suppression motions are part of the pretrial stage, after discovery and before a plea or trial. See the federal case process for every stage, and federal investigations for how search warrants are issued and carried out. Our guide to federal robbery charges discusses how Chatrie arose from a robbery case.

How can Criminal Center help with a suppression issue?

If you or someone you love has been charged after a search, a phone seizure or an interview with agents, a lawyer can review the warrant, the affidavit and the discovery to see whether a motion to suppress has a basis. Criminal Center is a boutique federal criminal defense firm. We take on a limited number of cases at a time, so each one gets close, personal attention. See federal criminal defense for how we work.

Book a consultation and tell us what happened.