Using the Motion to Suppress in a Criminal Defense Case

A successful motion to suppress can make a critical difference in your criminal defense case. With a motion to suppress, your attorney may be able to prevent certain evidence from being used against you during your trial. As part of your defense strategy, a suppression motion may result in the prosecutor’s case being dismissed or give you an advantage in plea negotiations.

What Is a Motion to Suppress?​

A motion to suppress is a formal request to have certain evidence suppressed, or excluded, from trial. It is a pre-trial motion used by defense teams, meaning the request is made before the trial begins. It is based on the exclusionary rule – a legal principle recognizing that the government should not be able to benefit from the evidence that was obtained by breaking the rules. Some examples include searching a home without a warrant in violation of the Fourth Amendment or coercing a confession in violation of the Fifth Amendment.

Motion to Suppress vs. Motion in Limine

A motion in limine is similar to a motion to suppress, but has a broader scope in application. Motions in limine can be used in civil cases as well as criminal cases, and may apply to evidence that was even gathered legally. A motion in limine is based on evidentiary rules intended to balance the need for relevant evidence against evidence that is unfairly prejudicial or otherwise problematic. Motions in limine can be filed based on rules of evidence and practical concerns; they do not require a showing that constitutional rights have been violated.

What Are the Grounds for a Motion to Suppress?

Examples for grounds for a motion to suppress might include:

Unlawful search evidence: Law enforcement must have a warrant before searching your possessions, with exceptions for evidence in plain view and exigent circumstances.

Miranda violations: Established by the case Miranda v. Arizona, your Miranda rights include the right to remain silent as well as the right to an attorney. If you were not informed of these rights while in custody prior to interrogation, your subsequent statements may be able to be suppressed from trial.

Coerced confessions: If a statement was obtained through threats, prolonged interrogation, denial of basic needs, or psychological pressure that overbore your will, the court may exclude it.

Fruit of the Poisonous Tree: Say that police illegally tapped your phone, and from this, they obtain further evidence about an in-person meetup that they connect to your case. This additional evidence, because it was obtained from a first illegal search, can now be considered “fruit of the poisonous tree.” This means that it should also be suppressed from the court, because the police would not have known to follow you without the initial illegal wiretap.

Common Evidence Challenged in a Motion to Suppress

• Emails and text messages
• Drugs or guns found through illegal stops
• Witness statements or confessions
• Photographs or videos
• Blood or hair samples
• Field sobriety tests

These challenges are particularly common in traffic-related cases. For instance, Kansas City DUI lawyers frequently use motions to suppress to challenge field sobriety tests or breathalyzer results if a stop on I-70 or a local checkpoint lacked the necessary probable cause.

How a Motion to Suppress Hearing Works

Your criminal defense attorney will draft a motion to suppress and file it with the court that has jurisdiction over your case. The motion may contain proof of the unlawful evidence collection, supporting case law, as well as additional information about your case. The court may hold a hearing to gather testimony and other evidence relevant to the motion. Proof to support the motion might include missing information on search warrants, photos, or videotapes of unlawful police action, evidence from the illegal search or seizure, and more.

If a motion to suppress is granted, the prosecution may find its case seriously weakened. In some cases, the charges can even be dismissed or dropped due to a lack of evidence. 

How Often Does a Motion to Suppress Work?

Most courts are generally not keen to suppress evidence, but they are less happy having an entire case overturned because they allowed coerced or illegally obtained evidence to be used at trial. Whether a suppression motion will work often turns on facts, but a skilled defense attorney will be able to spot suppression potential in your case and set the stage for a favorable ruling. Your attorney can explain more to you about this incredibly powerful tool and when it may or may not apply.

The Strategic Impact of a Motion to Suppress

A motion to suppress is often the turning point in a criminal defense strategy because it attacks the foundation of the prosecutor’s case. Rather than arguing about guilt or innocence, this motion shifts the spotlight onto the conduct of law enforcement, ensuring that constitutional violations have real-world consequences in court. By successfully challenging the admissibility of key evidence—whether it is a weapon, drugs, or a confession—the motion effectively removes the tools the prosecution needs to prove their case beyond a reasonable doubt. Ultimately, filing a motion to suppress is the most direct way to hold the government accountable to the law, potentially transforming a complex legal battle into a case dismissal.