What Happens When Evidence Is Obtained Illegally? Staff Profile Picture
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Richard Meehan Jr. Profile Picture
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The acquisition and use of evidence are essential in shaping the outcomes of cases. What happens, however, when the very foundation of evidence is contaminated by illegal activity? The consequences of evidence obtained through unconstitutional means ripple through courtrooms, calling the justice system's integrity into question. 

In the United States, a mere 2 percent of criminal cases make it to trial. Yet, even among this limited number, the majority of defendants are found guilty. In these instances, ensuring the legality and integrity of evidence is essential. Even in the face of overwhelming odds, safeguarding defendants' rights is a cornerstone of justice.

This article delves into the intricate landscape of illegally obtained evidence, exploring its impact on criminal trials and the indispensable role that criminal defense attorneys play in protecting defendants' rights. Through real-world examples, legal insights, and examining the exclusionary rule's dynamics, we will explore and explain the complexities of this critical facet of the justice system.

Understanding Illegally Obtained Evidence

Illegally obtained evidence refers to when information or materials are collected by law enforcement in violation of a defendant’s constitutional rights, primarily protected under the Fourth, Fifth, and Sixth amendments of the United States Constitution. 

Evidence that is obtained illegally, either through unauthorized searches, coerced confessions, or the invasion of privacy rights, is tainted. This includes situations where police conduct searches without a warrant, lack proper justification, or gather evidence through deceitful practices. Such actions undermine the criminal justice system's integrity and infringe upon an individual's rights.

The Impact of Illegally Obtained Evidence on Criminal Cases

Courts may, but don’t often, exclude such evidence from trial proceedings through the exclusionary rule, a legal principle aimed at deterring law enforcement misconduct. The most egregious actions will result in evidence being dismissed, but this, again, is not common.

The rule serves to prevent law enforcement from benefiting from their unconstitutional actions. Without illegally obtained evidence, the prosecution’s case might weaken or collapse, leading to possible dismissal of charges or reduced sentences for defendants. 

The potential consequences of admitting illegally obtained evidence can erode civil liberties, fostering a system where police operate outside the boundaries of the law. Moreover, it can negatively impact public trust in the justice system and undermine the principles of fairness in legal proceedings.

The Exclusionary Rule

The exclusionary rule is a legal principle that prohibits the use of illegally obtained evidence in criminal trials. It serves as a safeguard to protect a defendant's Fourth Amendment rights against unreasonable searches and seizures. When law enforcement acquires evidence through violations of these rights, such as conducting warrantless investigations or gathering information without proper justification, the exclusionary rule comes into play.

This rule ensures that evidence tainted by unconstitutional actions is suppressed and excluded from trial proceedings. Its purpose is twofold: 

  • To deter law enforcement misconduct by rendering unlawfully obtained evidence inadmissible.

  • To uphold the integrity of the justice system.

The exclusionary rule promotes fairness and accountability in legal proceedings by preventing the prosecution from benefiting from illegal actions. As a result, defendants are shielded from the potential harm of using evidence obtained through violations of their constitutional rights, ultimately preserving the principles of due process and maintaining the public’s confidence in the criminal justice system. 

Exceptions to the Exclusionary Rule

The exclusionary rule is designed to prohibit the use of illegally obtained evidence in criminal trials. However, several exceptions allow such evidence to be admitted under specific circumstances. The following list details these exceptions and their potential effects on a criminal case.

Inevitable Discovery Exception

This exception states that the evidence may be admissible if the prosecution can establish that the illegally obtained evidence would have been discovered through lawful means regardless of the unconstitutional actions. 

For example, if an illegal search yields evidence but later reveals that a valid search warrant would have been obtained anyway, the evidence might be considered admissible. This exception may mitigate the impact of the exclusionary rule by allowing evidence that would likely have been found legally.

An Example of the Inevitable Discovery Exception

To illustrate further, consider a hypothetical situation where law enforcement officers investigate a suspected drug trafficking operation. They received a tip from a confidential informant that a suspect was running a large-scale drug operation from his residence. The officers decide to conduct a warrantless search of the suspect’s home based solely on the informant’s tip, which, under normal circumstances, would be illegal. During the illegal search, the officers find a substantial amount of illegal drugs – all of which are seized as evidence. The suspect is arrested and charged with drug trafficking.

The suspect’s defense attorney argues that the evidence should be suppressed because it was obtained through an illegal search, violating their Fourth Amendment rights. In response, the prosecution invokes the inevitable discovery exception.

They present evidence to the court that before the illegal search, police had conducted a separate, legitimate investigation into the defendant’s drug activities. This investigation revealed valuable information about their involvement in drug trafficking, including surveillance footage of him meeting with known drug dealers, financial records indicating large cash transactions, and statements from witnesses who had seen suspicious activity at his residence.

In this case, the inevitable discovery exception could apply. The evidence would have been inevitably discovered through a legal search warrant, as the officers were already in the process of obtaining one based on legitimate investigative work. The illegal search merely accelerated the process, and the evidence would have been lawfully seized anyway.

Good Faith Exception

When police conduct a search or seizure based on a warrant that they genuinely believed was valid, the evidence obtained might still be admissible under the good faith exception. Even if the warrant later turns out to be invalid due to technical errors, if officers acted in good faith relying on the warrant, the evidence may not be suppressed. This exception prevents the exclusionary rule from punishing officers for honest mistakes and may impact cases where procedural warrant errors occur.

An Example of the Good Faith Exception

For instance, suppose a police officer conducting a cybercrime investigation executes a search warrant with a technical error in the address, inadvertently searching the wrong location. However, despite the error, the officer still finds evidence of criminal activity. 

When the case goes to court, the prosecution argues for the good faith exception, contending that the officers acted in reliance on the warrant issued by a judge, unaware of the error. The court may apply the good faith exception, as the officer’s actions were in line with the law, and the warrant’s technical error was a court staff mistake. Evidence obtained during the search may be admissible, given the officer’s genuine belief in the warrant’s validity.

Independent Source Exception

Suppose evidence has been obtained through legal and illegal means, but the lawful source is shown to be separate from the illegal one. In that case, the evidence may be admissible under the independent source exception. Accordingly, the prosecution might be unable to suppress evidence if it can show that the evidence was gathered from an untainted source. This exception can diminish the effect of the exclusionary rule when there are multiple paths to obtaining the evidence. 

An Example of the Independent Source Exception

To illustrate, imagine a scenario where police officers suspect a particular residence is being used for criminal activity. Without a proper search warrant, they conduct an illegal search and find a substantial amount of illegal drugs. However, later on, the officers managed to gather enough evidence and information to obtain a valid search warrant for the same residence through proper channels. 

In this case, the independent source exception could be relevant. If the prosecution can demonstrate that the information used to obtain the valid search warrant was completely separate from the initial illegal search, the evidence seized during the lawful search might be admissible in court. 

Attenuation Doctrine

This provision permits the introduction of evidence if the link between the unlawful actions of police and the evidence is sufficiently distanced or weakened, leading to the view that the blemish of wrongdoing has been effectively severed.

An Example of the Attenuation Doctrine

For example, consider a hypothetical scenario where an officer illegally enters a suspect’s garage, discovering stolen property. The defense may seek to suppress the evidence due to the illegal entry. However, the prosecution can argue the attenuation doctrine, explaining that after the unlawful entry, the officer secured the area and obtained a valid search warrant based on the information gathered. A lawful search subsequently recovered the stolen property. 

The court may apply the attenuation doctrine because the illegal entry was separated in time and circumstance from the lawful search under a warrant, making the evidence obtained through the warrant admissible, despite the initial illegal entry.

Your Rights and Protections

Facing illegally obtained evidence can be an intimidating experience for anyone accused of a crime. Fortunately, the U.S. Constitution provides rights and protections to ensure that individuals are treated fairly within the criminal justice system. 

Fourth Amendment Protection

Individuals have the right to be free from unreasonable searches and seizures by government authorities. This means that law enforcement generally needs a valid search warrant based on probable cause to search a person, their property, or their belongings. 

Search Warrant Requirement

The Fourth Amendment requires law enforcement to obtain a valid search warrant from a judge based on probable cause before searching. Searches may be unreasonable, and evidence could be suppressed without a warrant.

Probable Cause Standard

To obtain a search warrant, law enforcement must demonstrate to a judge that there is a reasonable belief that a crime has been committed, justifying the need to search for evidence. 

Notable Exceptions to the Warrant Requirement

While a warrant is typically required, exceptions such as exigent circumstances, consent searches, and the plain view doctrine allow police to search without a warrant.

Miranda Rights

Derived from the Fifth Amendment, individuals must be informed of certain rights upon arrest, as established in Miranda v. Arizona. This includes the right to remain silent and the right to an attorney – but, more importantly, statements made without these rights being read might be deemed inadmissible. 

Right to Remain Silent

The Fifth Amendment also provides the right against self-incrimination. Individuals have the right to remain silent and cannot be compelled to testify against themselves. This protects the accused from being coerced into providing incriminating statements. 

Right to Counsel

The Sixth Amendment guarantees the right to legal representation. Defendants have the right to an attorney during questioning and trial proceedings. An attorney can help protect their rights, including challenging the inadmissibility of potentially illegally obtained evidence. 

Right to Due Process

The Fifth Amendment guarantees that no person shall be deprived of life, liberty, or property without due process of law. This includes the fair and just treatment of individuals within the criminal justice system, ensuring their rights are upheld.

Legal Precedents and Case Examples

Mapp v. Ohio (1961)

In 1957, Dollree Mapp was living in Cleveland, Ohio, when her home was subjected to an illegal search by police officers looking for a suspect wanted in connection to a bombing. The officers did not possess a valid search warrant and forcibly entered Mapp's home. While they did not find the bombing suspect, they discovered obscene materials and arrested Mapp for having them, which was prohibited under Ohio law at the time. 

Mapp’s case eventually reached the Supreme Court. Her defense argued that the evidence of the obscene materials should be excluded from trial because it was obtained through an unconstitutional search and seizure. The central question before the court was whether the exclusionary rule should be extended to state criminal proceedings. 

Supreme Court Decision

In a landmark decision, the U.S. Supreme Court ruled in favor of Mapp. The court held that the Fourth Amendment's prohibition against unreasonable searches and seizures applies to state actions through the Fourteenth Amendment Due Process Clause. This ruling extended the exclusionary rule to state criminal trials, ensuring that evidence gathered in violation of a person's Fourth Amendment rights could not be used against them in state court. 

This ruling significantly strengthened the protection of individuals against illegal searches and seizures by providing a means to exclude evidence obtained through such actions. Theis decision had far-reaching implications, leading to increased scrutiny of law enforcement practices, and fostering a culture of accountability within the criminal justice system.

Brown v. Illinois (1975)

In 1968, defendant Edward Brown was arrested by Chicago police officers without a valid search warrant. Following the arrest, Brown was taken to the police station where, within two hours, he confessed to a murder. The confession was given after being read his Miranda rights, leading his attorney to argue that Brown's confession resulted from the illegal arrest and should be excluded under the exclusionary rule. The defense contended that the confession was a direct product of the initial unlawful action and was, therefore, tainted by a Fourth Amendment violation.

Supreme Court Decision

In a unanimous decision, the U.S. Supreme Court ruled that while Brown’s arrest was indeed unconstitutional, the subsequent confession was admissible under the attenuation doctrine. The Court introduced the concept that the connection between the initial illegal action (in this case, the unlawful arrest) and the evidence (Brown’s confession) could be sufficiently attenuated by factors such as the passage of time, intervening events, and the Miranda warnings. 

The Court acknowledged that although the arrest was a significant factor contributing to the confession, the Miranda warnings given and the two-hour time gap between the arrest and the confession created a break in the causal chain. As a result, the confession was deemed obtained by means independent of the initial Fourth Amendment violation.

This case established the attenuation doctrine as a factor in determining the admissibility of evidence obtained after an unlawful action. It recognized that the blemish of an illegal action might be weakened by intervening factors, leading to the conclusion that the evidence should not be automatically excluded. 

The Role of Your Criminal Defense Attorney

An experienced defense attorney can meticulously examine every facet of your case to construct a compelling defense strategy. They’ll exploit procedural errors, challenge the legality of searches, and ensure your rights remain unviolated. The outcome of your case might hinge on their ability to expose the unlawfully obtained evidence's weaknesses, potentially leading to reduced charges, case dismissal, or a more favorable plea bargain. For these reasons, it’s essential to research attorneys in your area who possess the following qualities.

Expertise in Constitutional law

A proficient defense attorney should understand constitutional rights significantly, particularly the Fourth Amendment's protection against unlawful searches and seizures. Their knowledge of legal precedents can aid in identifying violations and building a solid defense.

Analytical Skills

An attorney’s ability to dissect the circumstances surrounding the evidence is crucial. They can pinpoint procedural errors, lack of probable cause, and unauthorized searches, forming the basis for challenging the evidence’s admissibility. 

Experience in Exclusionary Rule Exceptions

Exceptional defense attorneys comprehend the nuances of exceptions to the exclusionary rule, like the inevitable discovery or attenuation doctrines. Their skill in presenting arguments that evidence would have been discovered legally or that the connection between the evidence and the illegal action is weak can influence the court’s decision. 

Strong Negotiation Skills

Beyond the courtroom, a capable attorney can negotiate with prosecutors to seek favorable resolutions, especially when evidence suppression weakens the prosecution's case.

How To Find the Best Criminal Defense Attorney For Your Case

Navigating a legal battle involving potentially illegally obtained evidence demands the guidance of a skilled defense attorney.’s Concierge Service and Criminal Defense Attorney Directories is an excellent resource to aid you in finding the lawyer to suit your unique needs.

Our meticulous review process ensures that you're matched with the best-qualified attorneys in your metro area. Our team goes beyond surface-level evaluations, delving deep into their credentials, qualifications, awards, and licenses. We analyze review data precisely, guaranteeing that the attorneys we recommend have an exemplary criminal defense reputation. 

With’s Concierge Service, you’re not alone in this challenging time. We provide tailored guidance and support, understanding the gravity of your situation. Our Criminal Defense Attorney Directories grant you direct access to professionals with a proven track record in combating illegally obtained evidence. Your rights deserve to be protected, and we’re here to make that happen.

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Richard Meehan Jr. Profile Picture

Richard Meehan Jr.Reviewer

Rich Meehan is a national board certified criminal trial specialist who practices criminal defense in Connecticut. He is a fellow of the American College of Trial Lawyers and the International Academy of Trial Lawyers. Visit: