Jeremy Rosenthal | June 12, 2026 | Criminal Defense
Evidence is one of the most important parts of any criminal case. However, prosecutors cannot use evidence that was obtained in violation of a defendant’s constitutional rights. When law enforcement gathers evidence unlawfully, a criminal defense attorney may ask the court to exclude it through a motion to suppress.
In some cases, suppressing key evidence can significantly weaken the prosecution’s case.
What Is a Motion to Suppress Evidence?
A motion to suppress evidence is a legal request asking a judge to prevent certain evidence from being introduced at trial. The motion argues that law enforcement officers obtained the evidence in a way that violated the defendant’s constitutional rights.
If the judge grants the motion, the prosecutor may be prohibited from using the evidence against the defendant. Depending on the circumstances, this can affect the outcome of the entire case.
Why Is Evidence Sometimes Suppressed?
Evidence is typically suppressed when police officers violate constitutional protections during an investigation. The Fourth Amendment protects individuals from unreasonable searches and seizures, while the Fifth Amendment protects individuals from being compelled to testify against themselves.
For example, evidence may be excluded if officers conduct an unlawful search, seize property without proper legal authority, or obtain a confession through improper methods. Courts suppress evidence to protect constitutional rights and discourage unlawful police conduct.
Common Types of Evidence That May Be Suppressed
A motion to suppress can apply to many different types of evidence, including:
- Drugs, weapons, or other physical evidence found during an illegal search
- Statements or confessions obtained unlawfully
- Evidence recovered from a cell phone, computer, or other electronic device
- Witness identifications resulting from improper police procedures
- Evidence discovered after an initial constitutional violation
Whether evidence can be suppressed depends on the facts of the case and how the evidence was obtained.
What Is the Exclusionary Rule?
The exclusionary rule prevents prosecutors from using evidence obtained through constitutional violations. The rule is designed to hold law enforcement accountable and encourage compliance with constitutional requirements.
Without the exclusionary rule, police officers would have less incentive to follow the law when conducting searches, seizures, and interrogations. By excluding improperly obtained evidence, courts help preserve the integrity of the criminal justice system.
The “Fruit of the Poisonous Tree” Doctrine
The “fruit of the poisonous tree” doctrine expands on the exclusionary rule. Under this principle, evidence derived from an unlawful search, seizure, or arrest may also be excluded.
For example, if officers conduct an illegal search and discover information that leads them to additional evidence, the newly discovered evidence may also be inadmissible. In other words, evidence that grows out of a constitutional violation may be tainted by the original misconduct.
When Can a Motion to Suppress Be Filed?
A motion to suppress is generally filed before trial. Criminal courts have deadlines for filing pretrial motions, so it is important to address potential constitutional violations as early as possible.
Waiting too long could limit a defendant’s ability to challenge the evidence. An attorney can review the circumstances of the arrest and determine whether grounds exist for filing a suppression motion.
What Must Be Proven at a Suppression Hearing?
If a motion to suppress is filed, the court may schedule a suppression hearing. During the hearing, the defense and prosecution can present evidence and legal arguments regarding the challenged evidence.
The defense must identify the constitutional violation and explain why the evidence should be excluded. Prosecutors may argue that the officers acted lawfully or that an exception applies. After reviewing the facts and applicable law, the judge will decide whether the evidence can be used at trial.
Why Hiring a Criminal Defense Lawyer Is Important
Motions to suppress often involve complex legal issues and detailed constitutional analysis. An experienced criminal defense lawyer can help by:
- Reviewing how the police obtained the evidence
- Identifying potential violations of your constitutional rights
- Filing a motion to suppress when appropriate
- Challenging unlawful searches, seizures, or interrogations
- Questioning witnesses at a suppression hearing
- Arguing that illegally obtained evidence should be excluded
Even a single piece of suppressed evidence can dramatically change the strength of the prosecution’s case. Having knowledgeable legal representation can help ensure that your rights are protected throughout the criminal process.
Contact Texas Defense Firm to Schedule a Confidential Consultation With a McKinney Criminal Defense Attorney
If you’ve been charged with a crime in McKinney or its surrounding areas and need legal help, contact our skilled criminal defense attorneys at Texas Defense Firm. Schedule a confidential consultation today to discuss your case and protect your rights.
We proudly serve Collin, Denton, Kaufman, and Rockwall counties and the surrounding areas. Visit our law offices at:
Texas Defense Firm – McKinney Office
7300 State Highway 121 Suite 400
McKinney TX 75070
(972) 369-0577
Available 24/7
