Illegally Obtained Evidence

 ILLEGAL EVIDENCE AND THE CONCEPTUAL FOUNDATIONS OF THE "EVIDENCE PROHIBITION" THEORY

Criminal procedural law aims not only to prove the existence of a crime but also to conduct this process in accordance with the principles of the "rule of law." In this context illegally obtained evidencelies on that fine and tense line between the principle of investigating the material truth and the protection of the fundamental rights and freedoms of the individual. In modern legal systems, the understanding of "reaching the truth at all costs" has given way to the principle of "reaching the truth only through means permitted by law." This fundamental paradigm shift is also reflected in the Turkish legal system in Article 38/6 of the Constitution and Articles 206/2-a, 217/2, and 230/1-b of the Code of Criminal Procedure (CMK).

1. The Concept and Classification of Illegally Obtained Evidence

illegally obtained evidenceis data that, by virtue of its method, means, or process of acquisition, constitutes a violation of the normative rules prescribed by the legal system. However, this definition gives rise to discussions in legal doctrine regarding "absolute violation" and "relative violation." For evidence to be deemed illegal, it is not sufficient for it to simply be contrary to the law; it must also be contrary to constitutional principles, international conventions, and general principles of law. Illegally obtained evidenceis "forbidden fruit," undermining the purity of the judicial process, casting a shadow on the fairness of the trial, and, as a rule, should not be used as the basis for a judgment.

2. Theory of Evidence Prohibitions: Prohibitions on Statement and Evaluation

In legal doctrine, the issue of illegally obtained evidence "Prohibitions on Evidence" (Beweisverbote) . This theory is divided into two main axes:

1. Prohibitions on Obtaining Evidence (Interrogations): This refers to illegalities in the evidence-gathering phase. For example, an interrogation obtained through torture, ill-treatment, deception, or unlawful promises, or a search of a residence without a court order, constitutes a violation of the prohibition on obtaining evidence. Here, the state, while exercising its sovereign power, has exceeded the boundaries set by law.
2. Prohibitions on the Evaluation of Evidence: This refers to the prohibition against using certain evidence as the basis for a judgment, even if it was obtained lawfully. For example, statements obtained from someone who has the right to refuse to testify, without informing them of this right, fall under the prohibition on evaluation even if they contain a technical error in their method of acquisition. However, the main issue is the obligation for the court to "disregard" evidence obtained illegally.

3. The Fruit of the Poisonous Tree Doctrine

Originating from American law and profoundly influencing both continental European and Turkish law, this doctrine describes the "contagious" effect of illegality. If evidence is obtained through an illegal method (like the "poison tree"), all subsequent secondary evidence derived from it (like the "fruit") is also considered illegal. illegally obtained evidence invalidates the entire process from beginning to end. For example, a drug found during a second "legal" search based on information in a notebook found during an illegal search is considered "poisoned fruit" because the first search was illegal, and therefore cannot be used as evidence.

4. Constitutional and Legal Basis: Absolute Prohibition Regime

Turkish law adopts a "pure prohibition" regime regarding illicit evidence

• Article 38/6 of the Constitution: "Findings obtained illegally cannot be accepted as evidence." This provision does not grant even the legislative body the authority to enact laws permitting the use of illegally obtained evidence.
• Article 217/2 of the Code of Criminal Procedure states: "The alleged crime may be proven by any evidence lawfully obtained." The opposite meaning of this article implies that no evidence obtained illegally can be considered as proof.

This absolute stance has been repeatedly emphasized in the decisions of the Turkish Court of Cassation Criminal General Assembly: "Evidence obtained through unlawful methods cannot be used as the basis for a judgment, regardless of its effect on proving the crime."

5. The Balance Between Material Reality and the Rule of Law

The aim of criminal procedure is to reach the material truth. However, perjured evidence reminds us that this aim is not limitless. If, in a murder case, the killer's weapon is found through an illegal search, using that weapon as evidence by saying, "the weapon is there, and this is the real killer," while seemingly delivering justice in the short term, undermines the foundations of the rule of law in the long term. The exclusionary rule is the greatest deterrent against law enforcement and judicial authorities acting outside the law.

 TYPES OF ILLEGALITIES, PROCEDURAL VIOLATIONS, AND THE DYNAMICS OF INCIDENTAL EVIDENCE

In criminal proceedings, the evidence gathering phase is the moment when the state makes the most aggressive intervention in an individual's private sphere. The legitimacy of this intervention depends solely on the condition of "lawfulness." Administered evidenceoften arises from law enforcement agencies neglecting procedural rules during judicial searches, seizures, or surveillance activities using technical means. This section analyzes, with technical depth, the most common forms of irregularities encountered in judicial practice and the fate of such evidence.

2.1. The Debate on Absolute and Relative Illegality

In Turkish legal doctrine and the practice of the Supreme Court, the distinction between "absolute illegality" and "relative (insignificant) illegality" has been debated for a long time.

• Absolute Violation of the Law: These are “serious” violations that infringe on fundamental rights, such as confessions obtained through torture or searches conducted without a court order. These are indisputably excluded.
• Relative Legal Irregularities: These are "formal" errors in the search report, such as the absence of two witnesses or the incorrect recording of the time.

However, the 2001 constitutional amendment and the current Code of Criminal Procedure regime have largely eliminated this distinction. illegally obtained evidence ; any data that contradicts the mandatory provisions of the law is considered "illegal" and excluded, regardless of its magnitude. For a state governed by the rule of law is not a system where minor procedural errors are ignored "in the name of justice."

2. Procedural Errors in Judicial Search and Seizure

The search constitutes a direct infringement of the rights to privacy and the inviolability of the home. Any deviation from this process places the obtained evidence in the category of contraband

• Decision-Making Mechanism: According to Article 119 of the Code of Criminal Procedure, a search warrant is normally issued by a judge. In cases where delay would be detrimental, a written order from the public prosecutor is required. If a search of a residence is conducted on the order of a law enforcement officer when the prosecutor is available, the seized drugs or weapons cannot be used as the basis for a judgment, even if they constitute the strongest evidence of the crime.
• Persons Required to Be Present During a Search: During searches of a residence or workplace, the owner or representative of the property, or if neither is available, two neighbors, must be present. Violation of this rule is considered by the Supreme Court as one of the most fundamental procedural errors that renders evidence "illegal."

3. Incidental Evidence and its Limitations (Code of Criminal Procedure, Article 138)

Incidental evidence refers to evidence obtained during a search or surveillance operation conducted to investigate a crime, which is unrelated to the ongoing investigation but raises suspicion that another crime has been committed .

• Catalog Crime Requirement: For incidental evidence to be used, the newly discovered crime must also be among the "catalog crimes" (Article 135/8 of the Code of Criminal Procedure). For example, if a confession of theft is accidentally discovered during a wiretap related to a bribery investigation, this recording cannot be used as evidence because theft is not a catalog crime.
• Immediate Notification Obligation: Law enforcement or prosecutors who come across incidental evidence must secure the information without delay and request a new court order. Data collected without properly following the "incidental evidence protocol" is included in the pool of illegally obtained evidence

4. Monitoring and Detection of Communications Using Technical Means

In the digital age, contradictory evidence most often arises from communications made via telecommunications.

• The Principle of Last Resort: Interception, listening, and recording of communications are measures that can only be resorted to as a "last resort" (ultima ratio) when there is no other way to obtain evidence. If direct wiretapping is used when evidence of a crime could be obtained through other means, this decision and the resulting recordings become unlawful.
• Violations of Time Limits and Extensions: Exceeding the time limits specified in the judge's decision or granting extensions without justification are "procedural poisons" that render the obtained audio recordings outside the scope of the trial.

5. Authenticity vs. Legality of Evidence

A point that is often confused is the “authenticity” of evidence versus its “legality.” An audio recording may not be a montage and may prove that the defendant clearly confessed to the crime (its authenticity). However, if this recording was obtained through an illegal method (e.g., unauthorized secret recording), the “authenticity of its content” does not save that evidence. illegally obtained evidence : not everything that is true is evidence; only everything that is legal is evidence.

PROHIBITED INTERROGATION METHODS, LEGAL COUNSELING, AND THE LEGAL VALIDITY OF STATEMENT TRANSCRIPTS

In criminal proceedings, the "suspect" or "defendant" is not merely an object of accusation, but an active subject of the proceedings. Therefore, the free will of the individual is an indispensable condition of the rule of law. illegally obtained evidenceconsists of statements obtained through methods that impair the suspect's will. Articles 147 and 148 of the Code of Criminal Procedure constitute the constitution of this process.

1. Prohibited Methods that Impair Freedom of Expression (Article 148 of the Code of Criminal Procedure)

The legislator has listed the methods that are absolutely prohibited during questioning and interrogation not exhaustively, but illustratively. Any interference that hinders free will places the obtained statement in the category of illegitimate evidence

• Physical and Psychological Interventions: Torture, ill-treatment, drug administration, exhaustion, and sleep deprivation are the most severe violations. Whether the statement obtained in this way is "true" or not is irrelevant; any statement obtained through this method is "absolutely" null and void.
• Deception and Unlawful Promises: Guiding a suspect with false statements such as "If you confess, you will be released" or "Your friend told everything, you tell too" invalidates the testimony. The state cannot use deception against its citizens.
• Coercion and Threats: This includes not only physical violence, but also psychological pressure involving threats of harm to a person's loved ones or the destruction of their social status.

2. Fate of Statements Taken Without the Presence of the Defense Counsel

In the Turkish criminal justice system, the right to defense is a cornerstone of a fair trial. This right is particularly vital during the law enforcement phase.

• Mandatory Legal Representation and Informed Conduct: Statements obtained without informing the suspect of their rights or by preventing them from requesting legal counsel constitute illegally obtained evidence
• Confirmation Before a Judge Requirement: According to Article 148/4 of the Code of Criminal Procedure, a statement taken by law enforcement without the presence of a defense attorney cannot be used as the basis for a judgment unless it is confirmed by the suspect or defendant before a judge or court. In other words, the moment the defendant says in court, "I didn't have a lawyer with me at the police station, I don't accept that statement," that record legally becomes a "dead" document.

3. Irregularities Under the Concepts of "Unsigned Minutes" and "Interview"

In practice, law enforcement officers sometimes attempt to gather information from suspects through a conversation, known as an "interview" or "preliminary discussion," before proceeding with the formal statement process.

• Evidential Value of Interviews: Our legal system does not have a defined method of obtaining evidence called "interview." Notes taken during these interviews or confessions made by the suspect at that time are considered perjured evidence if they do not conform to formal interrogation procedures (such as reminding them of their rights, legal representation, etc.) .
• Record Keeping Procedure: Failure to sign every page of the statement record, the absence of records of those taking the statement, or inconsistencies in dates directly affect the validity of the document and, consequently, its legality.

4. The Court of Cassation's Stance on "Material Fact"

The Supreme Court's Criminal General Assembly illegally obtained evidence . According to the Supreme Court, "The fact that a statement obtained through an illegal method absolutely contributes to the defendant's confession of guilt or the proof (confirmation) of the crime does not justify accepting that statement as evidence." This approach is the most concrete manifestation of the principle that "a state governed by the rule of law is not a state that commits crimes to catch criminals." If law enforcement obtains a confession using prohibited methods, this confession should be "disregarded" by the court, and the reasoned judgment should not refer to this evidence in any way.

5. Defense Strategy and the Request for “Exclusion of Evidence”

During the trial process, the defense the "removal of evidence from the file" or its "not being used as a basis for the judgment" illegally obtained. According to Article 206/2-a of the Code of Criminal Procedure, the judge is obligated to reject evidence if it has been obtained illegally during the presentation phase. This rejection ensures that "contaminated" data is cleared at the beginning of the trial.

 DIGITAL EVIDENCE, SEARCHING IN INFORMATION SYSTEMS AND PROTECTING DATA INTEGRITY

The radical transformation of crime-committing methods through technology has elevated the concept of "digital evidence" to a central position in criminal procedure. However, digital data, by its very nature, is far more susceptible to manipulation, copying, and deletion than physical evidence. Therefore, data obtained from a computer file or mobile phone from falling into the category of contraband evidence, meticulous adherence to Article 134 of the Code of Criminal Procedure is essential.

1. Procedure for Search and Seizure in Information Systems (Code of Criminal Procedure, Article 134)

Searches conducted in digital media are subject to much stricter rules than general search regulations (Articles 116-119 of the Code of Criminal Procedure). The legislator, considering the sensitivity of digital data, has foreseen a special protection regime:

• Judicial Order Requirement: As a rule, a judicial order is required to conduct searches in information systems. In cases where delay would be detrimental, even if there is a written order from the public prosecutor, this order must be submitted for judicial approval within 24 hours. Any failure to follow this procedure will render all digital copies illegally obtained evidence
• Last Resort Principle: Just like in surveillance, the condition for searching information systems is that "there must be no other way to obtain evidence."

2. Image Acquisition (Forensic Copy) and Hash Value Critique

The only condition for digital data to be used as evidence in court is to prove that the data has not been "altered." This is only an image capture process.

• Hash Value (Digital Fingerprint): The "hash value" (MD5, SHA-1, etc.), which is a mathematical summary of the data on the device being searched, must be calculated at the time of the operation and recorded in the report. If law enforcement begins examining the device without taking an image of the device or determining its hash value, any data obtained from that device (correspondence, photos, log records) contraband evidence . This is because it is impossible to verify whether data has been tampered with if an image of the device has not been taken.
• Providing a Copy of the Data Record to the Suspect: The law mandates that a copy (backup) of the data record obtained during a search be provided to the suspect upon request. This serves as a safeguard proving that the data was not "added later."

3. Remote Access and Password Restriction

If law enforcement is unable to decrypt the password or access the data on a seized device, necessary actions can be taken to decrypt the system. However, accessing cloud storage accounts (iCloud, Google Drive, etc.) without the suspect's consent and exceeding the scope of a court order illegal evidence. If the order only covers "data on the device," retrieving data from remote servers to which the device is connected constitutes exceeding the scope of authority.

4. WhatsApp, Social Media, and the "Screenshot" Problem

the most common of contraband evidence is the presentation of correspondence between the parties via screenshots.

• Data Integrity Concern: A screenshot is an image file that can be easily manipulated. If this image is not verified by an expert using the original device and its metadata, it cannot alone constitute grounds for conviction.
• Unlawful Seizure: Taking someone's phone without their consent and copying their WhatsApp conversations, secretly recording them, or using spyware constitutes "poisonous fruit." In Turkish judicial practice, even "recordings secretly taken from a spouse's phone" are considered illegitimate evidence in criminal cases

5. Timeline Analysis in Digital Evidence

A legally compliant digital examination must clearly establish when the data was created, modified, and deleted. If this chronological consistency cannot be established in the forensic report, or if there is suspicion that the system clocks have been tampered with, this should be challenged by the defense on the grounds of "the validity and illegality of the evidence.".

EVIDENCE OBTAINED BY PRIVATE INDIVIDUALS, LEGAL EXCEPTIONS, AND CURRENT JUDICIAL DOCTRINE

"illegally obtained evidence" often brings to mind irregular actions by the state (law enforcement), in practice, the situation regarding data obtained independently by individuals presents a legal labyrinth. As a rule, the procedural rules that the state is obliged to follow do not apply equally to private individuals; however, this does not legitimize private individuals collecting evidence by committing crimes or severely violating fundamental rights.

1. Secret Recordings Made by Private Individuals and the "Instant Event" Exception

The Supreme Court uses a very specific criterion when reviewing audio or video recordings made by private individuals for "illegality.".

• Risk of Loss of Evidence: If a person records an incident in a sudden, unexpected situation where they have no opportunity to contact law enforcement, with the aim of proving a crime committed against them (threat, insult, blackmail, etc.), this recording of contraband evidence . The purpose here is the individual's attempt to prove the injustice they suffered "accidentally and unexpectedly."
• Prohibition of Premeditated Arrangements: If a person has made prior preparations to interrogate the other party, equipped the environment with listening devices, or used spyware, this exceeds the boundaries of "self-defense," and the evidence obtained cannot be used in court.

2. Spyware and Interference with Privacy

In criminal cases, particularly those related to divorce proceedings, the use of spyware installed on each other's phones or data obtained by hacking social media account passwords frequently comes to the forefront.

• Absolute Prohibition: Data obtained by intruding on someone's private communication space without their consent illegal evidence . Findings obtained through this method constitute a violation of Articles 20 (Privacy) and 22 (Freedom of Communication) of the Constitution.

3. The Constitutional Court (AYM) and the Court of Cassation's "Reasoned Decision" Requirement

The Constitutional Court, in cases brought before it through "individual applications," meticulously examines the local courts' approach to evidence that is contrary to the law

• Exclusion Requirement: When rendering its judgment, the court must clearly justify why it has excluded or accepted as lawful evidence if such evidence is found to be illegally obtained.
• Right to a Fair Trial: If a court uses illegally obtained evidence as the sole and decisive proof, this is considered a violation of the "right to a fair trial" under the European Convention on Human Rights (ECHR) and the Constitution.

4. The Timing of Alleging the "Illegality" of Evidence

During the trial process, illegally obtained evidence can be presented at any stage. In fact, if a judge notices that evidence in a case before them is illegal, they are obligated to consider it ex officio (on their own initiative), even if the parties do not object. However, from a defense strategy perspective, requesting the rejection of evidence at the beginning of the hearing ensures that the rest of the trial is free from this tainted data.

CONCLUSION 

The issue of illegally obtained evidence acts as a "safety valve," guaranteeing that every member of society lives under the protection of the law, despite the risk of a criminal going unpunished. The principle that "the fruit of a poisonous tree is also poisonous" reminds us that justice is not just an outcome, but a process.