The top 5 legal grounds for the suppression of evidence are that
- the evidence was obtained in an unreasonable search done without a warrant,
- the police obtained evidence in violation of your right to a lawyer,
- you were not properly Mirandized,
- the police had a search warrant, but it was defective or deficient, and
- police failed to preserve the chain of custody of the evidence.
There are other ways to suppress evidence, as well. However, these are some of the most common and important.
In this article, our criminal defense lawyers will discuss each of these legal arguments in more depth.
1. Unreasonable search without a warrant
Perhaps the most common way for evidence to get suppressed is if it was obtained by law enforcement during an unreasonable search that was done without a warrant. The Fourth Amendment to the U.S. Constitution forbids unreasonable searches and seizures.
Many state constitutions also forbid them. If law enforcement violates your Fourth Amendment rights, any evidence they find as a result of the violation will be kept out of court.
Police conduct a search when they invade your reasonable expectation of privacy in order to find evidence of a crime.1 Police can conduct 2 types of searches:
- pursuant to a search warrant, or
- warrantless searches.
Warrant exceptions
When done without a warrant, it is up to law enforcement to show that it was a reasonable search.2 They can do this by showing that the search fell within a recognized exception to the warrant requirement. The most common of these warrant exceptions are:
- consent searches,
- searches incident to an arrest,
- vehicle searches,
- plain view searches,
- exigent circumstances,
- searches of open fields, and
- administrative searches.
So long as the search falls into one of these categories, police do not need a warrant to do it. However, if the search does not fall into a valid warrant exception, it is an unreasonable and illegal search. It violates your civil rights.
You can file a motion to suppress whatever evidence was obtained as a result of that violation. If successful, the evidence will be excluded from the trial against you.
2. Violation of the right to a lawyer
Under the Sixth Amendment to the U.S. Constitution, you as a criminal defendant have a right to an attorney.3 The right to a lawyer gets triggered when you are formally charged, or when law enforcement shifts from investigation to an accusation.4
Invoking your right to legal counsel
If you have a right to a lawyer, and you invoke it while being interrogated, police must provide access to an attorney.5 The invocation of your right to a lawyer has to be unambiguous.6 Until an attorney is present, police cannot interrogate you.7 If they do, it is a violation of your rights. If law enforcement obtains incriminating evidence from the violation, it can be suppressed.
You also have a right to a lawyer at other stages of the criminal justice system, like during a police lineup or suspect identification.8
Waiver of your right to legal counsel
However, it is important to note that you can waive your right to a lawyer.9 It is up to the prosecutor to prove that this waiver was done intentionally by you.10 Your waiver is only effective if you know that you are talking to a member of law enforcement.11
3. Violation of Miranda rights
As a criminal suspect, you have a Miranda right to be informed of your civil rights that come from the Fifth and Sixth Amendments of the United States Constitution. Under case law, police are required to inform you of these rights before a custodial interrogation. This is known as “Mirandizing” you. If you have not been Mirandized and are then subjected to custodial interrogation, incriminating information obtained during that interrogation may be suppressed.
The U.S. Constitution provides:
- the privilege against self-incrimination, also known as the right to remain silent, and
- the right to a lawyer.
In Miranda v. Arizona, the Supreme Court of the United States ruled that police must inform you of these rights. If they do not, it violates the Fifth Amendment and Sixth Amendment and any incriminating statements can be suppressed.12
Miranda warnings
Police inform you of your rights through a Miranda warning. The warning informs you that:
- you have the right to remain silent,
- anything you say can be used against you in court,
- you have a right to talk to a lawyer, and
- a lawyer will be appointed for you, if you cannot afford one.
Many TV shows include Miranda warnings when law enforcement officers arrest someone on the show.
You only have to be given your Miranda warning before a custodial interrogation.
Custodial interrogation
Broadly speaking, you are in custody if you:
- are in police custody, or
- have been significantly deprived of your freedom of action.13
An interrogation is when police:
- subject you to an express line of questioning, or
- use words or actions known to be reasonably likely to get an incriminating response.14
4. Deficient or defective search warrant
Just because police have a search warrant does not mean that they can violate your civil rights. If police execute a search warrant that is defective or deficient, evidence obtained may be suppressed.
The Fourth Amendment to the U.S. Constitution states that search warrants are only to be issued for probable cause. They can also only be issued by judges or magistrates who are neutral and detached.15
It is up to the police to persuade a judge or magistrate that they have probable cause to believe that criminal activity is going on. Law enforcement has to show this by affidavits and sworn testimony. A search warrant will only be issued if the judge or magistrate agrees that there is probable cause.
Challenging search warrants
You can challenge search warrants in 2 ways. You can argue that it is:
- defective, or
- deficient.
Defective warrants
To show that the warrant was defective, you can challenge the probable cause underlying a search warrant. You can do this by filing a Franks motion.16 The court will hold a Franks hearing. At the hearing, you can challenge the issuance of the search warrant by showing that it:
- contains statements that were knowingly or intentionally false, or
- includes statements that show a reckless disregard for the truth.17
Deficient warrants
In order for a search warrant to be deficient, you have to show that it failed to adequately instruct officers executing it. This can happen when the warrant:
- does not specify what evidence is to be seized, and instead amounts to a “general warrant,” or
- fails to give an adequate description of the place to be searched.
Police misconduct
You can also suppress evidence that was obtained under a search warrant if police:
- exceeded the scope of the warrant, or
- seized evidence that was not listed in the warrant.
5. Chain of custody problems
Occasionally, evidence can be suppressed if police are not able to prove a chain of custody.
When police seize tangible evidence of a crime, they have to keep it secure. Tangible evidence can take the form of:
- a weapon,
- drugs,
- money,
- a photograph, or
- a car.
In order to present this type of evidence at trial, law enforcement has to show that they had possession of the evidence at all times. If there is a gap in the chain of custody, it undermines the reliability of that evidence. You may be able to get the evidence suppressed.
What happens if evidence gets suppressed?
Evidence that gets suppressed will be excluded from your trial. Prosecutors will not be able to present it against you.
This is known as the exclusionary rule.
In some cases, the suppressed evidence was crucial to the prosecutor’s case. Having it kept out of trial can doom the prosecutor’s case against you. When this happens, law enforcement might offer a better plea deal or may drop the criminal charges, altogether.
What is the fruit of the poisonous tree?
The fruit of the poisonous tree is a legal metaphor. It refers to evidence that was gathered after your civil rights were violated, but independently of the violation.
Under the metaphor, the unlawful search or seizure is the poisonous tree. Because the tree is poisoned by the violation of your rights, all subsequent evidence obtained – the fruit of the tree – is also tainted. Evidence tainted by the civil rights violation can be suppressed and excluded from the criminal trial.
For example: Police officers violate Tim’s constitutional rights by unlawfully entering his house. Tim tells them that Jonny is selling drugs. The police then lawfully enter Jonny’s house and find a controlled substance. Both Tim’s statements and the drugs found in Jonny’s house are fruit of the poisonous tree because they stemmed from the unlawful entry into Tim’s house.18
When is a motion to suppress evidence filed in a criminal case?
A motion to suppress evidence, also known as a suppression motion, can be made during the pretrial stages of the criminal proceedings. They are often made at the preliminary hearing, though they can be filed as early as the arraignment. Otherwise, they can trigger a pretrial hearing.
Whether you are facing misdemeanor or felony charges, it is crucial for you to have the legal representation of a criminal defense attorney from a reputable law office who understands this key piece of criminal procedure.
What is the burden of proof to win a motion to suppress?
In order to convince the court to grant a motion to suppress evidence, you need to prove your argument by “by a preponderance of the evidence.” This is the legal way of saying “more likely than not” or “more than 50% likely.”
Example: Jim, who is facing drug trafficking charges, asks the court to suppress the drugs as evidence. For the court to suppress the drugs, Jim would need to show that it is more likely than not that the police’s search and seizure of the drugs was illegal.
“By a preponderance of the evidence” is a much lower standard than “beyond a reasonable doubt,” which is the standard prosecutors have to meet in order to prove someone guilty at trial.19
Legal References:
- Katz v. United States, 88 S.Ct. 507 (1967).
- United States v. Jeffers, 342 U.S. 48 (1951).
- Brewer v. Williams, 430 U.S. 387 (1977).
- Moran v. Burbine, 475 U.S. 412 (1986).
- Messiah v. United States, 377 U.S. 201 (1964).
- Berghuis v. Thompkins, 560 U.S. 370 (2010).
- Maine v. Moulton, 106 S.Ct. 477 (1977).
- United States v. Wade, 87 S.Ct. 1926 (1967).
- Patterson v. Illinois, 108 S.Ct. 2389 (1988).
- Johnson v. Zerbst, 58 S.Ct. 1019 (1938).
- United States v. Henry, 100 S.Ct. 2183 (1980).
- Miranda v. Arizona, 86 S.Ct. 1602 (1966).
- Same.
- Rhode Island v. Innis, 100 S.Ct. 1682 (1980).
- Coolidge v. New Hampshire, 91 S.Ct. 2022 (1971).
- Franks v. Delaware, 438 U.S. 154 (1978). See also United States v. Veloz, 948 F.3d 418 (2020).
- Franks v. Delaware, 438 U.S. 154 (1978).
- Facts from Wong Sun v. United States, 83 S.Ct. 407 (1963).