What is a Catalog Crime? The Concept and Scope of Application of Catalog Crimes in Criminal Procedure Law

One of the most frequently asked questions in criminal procedural law is about the concept of " catalog crimes ." The term "catalog crimes" is often used, particularly in news reports, investigation processes, and assessments related to arrest warrants. However, in practice, this concept is often misunderstood. The designation of a crime as a catalog crime does not mean that it is a different type of crime from others. Catalog crimes are not separate crime categories in the Turkish Penal Code, but rather refer to crimes listed restrictively in the Code of Criminal Procedure for the purpose of applying specific protective measures

The primary purpose of regulations concerning cataloged offenses is to ensure the effective investigation of crimes that may have serious consequences for society and to allow for the application of certain protective measures when necessary. However, this does not mean that fundamental rights and freedoms can be restricted without limit in cases involving cataloged offenses. The guarantees regarding the right to personal liberty and security enshrined in the Constitution, as well as the principle of proportionality in the Code of Criminal Procedure, remain valid for cataloged offenses.

What is a catalog crime?

The term "catalog crime" is a doctrinal concept used to refer to the crimes listed restrictively in various articles of the Code of Criminal Procedure. Although there is no separate article in the law titled "catalog crime," this expression is used in practice because the crimes for which specific protective measures can be applied are listed individually.

In other words, a catalog crime is one of the crimes explicitly designated by law for the application of specific protective measures. Therefore, not every crime is a catalog crime. Similarly, there is not a single catalog for every protective measure. Different catalogs are prescribed for each measure, such as arrest, communication surveillance, deployment of undercover investigators, and monitoring with technical means.

Legal Basis for Catalog Crimes

The provisions regarding cataloged offenses are primarily found in the Code of Criminal Procedure No. 5271

The most common regulations are as follows:

• CMK Article 100 (Arrest)
• Articles 127 and 129 of the Code of Criminal Procedure (Certain seizure measures)
• CMK Article 133 (Appointment of a trustee to company management)
• CMK Article 135 (Interception and recording of communications)
• CMK Article 139 (Appointment of a secret investigator)
• CMK Article 140 (Monitoring with technical means)
• Article 248 of the Code of Criminal Procedure (Seizure of the fugitive's assets)

The offenses to which each regulation can be applied are listed separately. Therefore, the fact that an offense is a catalog offense for arrest purposes does not mean that wiretapping or the deployment of undercover investigators is also possible for the same offense. Each measure must be evaluated separately within the scope of its own article.

The Purpose of Catalog Crimes

In criminal proceedings, protective measures are those applied before a final conviction has been issued against a person and which constitute an interference with fundamental rights. Therefore, the legislator has regulated in detail the conditions under which these measures can be applied.

The aim of the catalog crime system is to facilitate the investigation of serious crimes while simultaneously preventing the arbitrary application of protective measures. This aims to both protect public order and safeguard individual rights.

Catalog of Offenses in Terms of Arrest (Article 100 of the Code of Criminal Procedure)

When the term "catalog crime" is mentioned in practice, the first regulation that comes to mind is Article 100 of the Code of Criminal Procedure.

Article 100/3 of the Code of Criminal Procedure establishes a presumption that grounds for arrest may exist for the offenses listed therein. However, this presumption does not automatically mean that an arrest warrant will be issued for everyone alleged to have committed a catalog of offenses. In each specific case, the judge must separately assess the strong suspicion of guilt, the principle of proportionality, and whether the arrest measure is truly necessary.

Some of the catalog of crimes included in Article 100 of the Code of Criminal Procedure are as follows:

• Genocide and crimes against humanity
• Migrant smuggling and human trafficking
• Intentional killing
• Torture
• Child sexual abuse
• Qualified sexual assault
• Manufacturing and trading of narcotic or stimulant substances
• Spoil
• Qualified theft
• Crimes against state security
• Crimes against the constitutional order
• Crimes of armed organizations

These crimes are among those deemed by the legislator to have more serious consequences for public safety.

Is Arrest Mandatory in Catalog Crimes?

One of the most common misconceptions in practice is that arrest is mandatory in catalog crimes.

This is not true.

The fact that a crime is included in the catalog of offenses does not automatically mean that arrest will be applied. Arrest is an exceptional protective measure under the Constitution and the Code of Criminal Procedure. Therefore, in each case, the judge must first assess whether there is strong suspicion of guilt, and then whether the arrest measure is proportionate. In cases where judicial control measures are sufficient, these measures may be ordered instead of arrest.

Strong Suspicion of Crime in Catalog Crimes

In cataloged crimes, the most fundamental requirement is strong suspicion of guilt.

A mere tip-off or abstract allegations are not sufficient for the application of protective measures. The evidence in the file must strongly indicate that the suspect may have committed the crime.

In this context;

• Witness statements,
• Camera recordings,
• Digital materials,
• HTS records,
• Expert reports,
• Physical surveillance records,
• Evidence obtained as a result of search and seizure operations

Legally obtained evidence such as this is evaluated together.

Even in cataloged crimes, the mere inclusion of the crime in the catalog is not sufficient for protective measures to be applied; the specific characteristics of the case and the evidence in the file also play a decisive role.

Catalog of Crimes in Terms of Communication Surveillance (Article 135 of the Turkish Criminal Procedure Code)

One of the most stringent protective measures in criminal proceedings is the monitoring of a suspect's or defendant's communications. This measure, which constitutes a direct interference with freedom of communication and the privacy of private life, can only be applied if the conditions specified in the law are met.

According to Article 135 of the Code of Criminal Procedure, in relation to certain crimes, the telecommunications of the suspect or defendant may be intercepted, recorded, or signal information may be evaluated. However, for this measure to be applied, there must first be strong suspicion of guilt based on concrete evidence, and it must be impossible to obtain evidence by any other means.

Article 135 of the Code of Criminal Procedure lists the crimes that allow for the monitoring of communications in a limited manner. These include:

• Intentional killing,
• Torture,
• Human trafficking,
• Migrant smuggling,
• Child sexual abuse,
• Manufacturing and trading of narcotic or stimulant substances,
• Forming an organization for the purpose of committing crimes,
• Crimes against state security,
• Crimes against the constitutional order

There are serious crimes such as these.

It is not possible to order the monitoring of communications for a crime not listed in the law, even if other conditions are met. In this respect, the catalog system serves as an important safeguard for the protection of fundamental rights and freedoms.

Catalog of Crimes in the Assignment of Undercover Investigators (Article 139 of the Code of Criminal Procedure)

Article 139 of the Code of Criminal Procedure allows for the deployment of undercover investigators in the investigation of certain serious crimes.

An undercover investigator is a public official assigned to investigate the activities of criminal organizations, gather evidence, and contribute to solving crimes without revealing their identity.

Because this measure may indirectly interfere with a person's private life and freedom of communication, it can only be applied to the catalog of offenses specified in the law.

Especially;

• Drug trafficking,
• Human trafficking,
• Crimes committed by armed organizations,
• Terrorist crimes,
• Forming an organization for the purpose of committing crimes

In crimes such as these, the deployment of undercover investigators may be considered.

However, the role of an undercover investigator is not to incite individuals to engage in criminal behavior, but to uncover existing criminal activity. Anything to the contrary could lead to arguments about illegally obtained evidence.

Catalog Crimes in Terms of Monitoring with Technical Means (CMK Article 140)

Technical surveillance is one of the protective measures that allows investigative authorities to record audio or video for the purpose of uncovering specific crimes.

This measure can only be applied to the catalog of offenses explicitly specified in the law.

In order to make a decision to monitor using technical means;

• The existence of strong suspicion of a crime,
• The impossibility of obtaining evidence in any other way,
• Obtaining a judge's decision

is required.

Because this measure constitutes a serious interference with the fundamental rights and freedoms of individuals, its scope of application has been kept quite limited.

Search and Seizure Measures in Catalog Crimes

Although search and seizure measures are not specific to cataloged crimes, they are frequently used procedures in investigations related to cataloged crimes.

Searches of a suspect's residence, workplace, vehicle, or other living spaces must comply with the procedural rules stipulated in the Code of Criminal Procedure.

Similarly, seizure orders may be issued for items, digital materials, or documents deemed to be connected to a crime.

However, if search and seizure operations are carried out unlawfully, the usability of the evidence obtained in court may become questionable. Therefore, it is of great importance to act in accordance with legal procedures in the application of protective measures.

Catalog of Crimes in Light of Constitutional Court and Supreme Court Decisions

A point commonly emphasized in the decisions of both the Constitutional Court and the Court of Cassation is that the catalog of offenses system does not automatically result in arrest or the application of automatic protective measures.

In numerous individual application decisions, the Constitutional Court has stated that the right to personal liberty and security can only be restricted if the legal conditions are met in the specific case. The mere fact that a crime is a catalog crime does not, by itself, justify restricting personal liberty. In addition, there must be facts indicating a strong suspicion of guilt, and the measure applied must be proportionate.

The Supreme Court similarly emphasizes that in cataloged crimes, the evidence in the case file must be carefully evaluated in order to apply protective measures. It is stated that decisions based on abstract reports, assumptions, or claims not supported by sufficient evidence may be unlawful.

High courts agree that protective measures are exceptional and should only be applied to the extent required by the investigation.

How should the presumption of arrest be evaluated in cataloged crimes?

In practice, the concept of "presumption of arrest" is used in relation to the catalog of offenses listed in Article 100 of the Code of Criminal Procedure. However, this presumption is not absolute and irrefutable.

The judge, in each case;

• whether there is strong suspicion of a crime,
• The status of evidence collection,
• The possibility of the suspect escaping,
• The possibility of destroying evidence,
• whether judicial control measures will be sufficient

They must be evaluated separately.

Therefore, in an investigation conducted under the scope of catalog crimes, it is possible to decide on judicial control measures instead of arrest if the conditions are not met.

Misinterpretations in Practice Regarding the Concept of Catalog Crime

There are some misconceptions in public opinion and in practice regarding the concept of catalog crimes.

The first misconception is that cataloged offenses constitute a separate group of crimes regulated in the Turkish Penal Code. However, cataloged offenses are simply a list of crimes for which specific protective measures can be applied, as defined in the Code of Criminal Procedure.

Another misconception is that arrest is mandatory in catalog crimes. However, arrest is an exceptional protective measure and requires a separate assessment for each specific case.

Furthermore, the idea that protective measures such as monitoring communications, deploying undercover investigators, or using technical surveillance can be applied to every catalog of crimes is incorrect. Each protective measure has its own legal requirements and its own specific catalog of crimes.

Conclusion

The concept of a "catalog of offenses" is a technical term in criminal procedural law that refers to crimes for which specific protective measures can be applied. These offenses are not regulated as a separate category in the Turkish Penal Code; rather, they are listed restrictively within the provisions relating to protective measures in various articles of the Code of Criminal Procedure. The inclusion of a catalog of offenses system, allowing for the application of measures such as arrest, communication surveillance, the deployment of undercover investigators, and monitoring through technical means, aims both to ensure the effective conduct of investigations and to limit interference with fundamental rights and freedoms within a legal framework.

However, the inclusion of a crime among the catalog of offenses does not mean that the relevant protective measures will be applied in every case. According to the fundamental principles of criminal procedure, conditions such as the existence of strong suspicion of guilt, the principle of proportionality, and the necessity of the measure must be evaluated separately for each specific case. The established decisions of the Constitutional Court and the Court of Cassation also adopt this approach, demonstrating that interventions in the right to personal liberty and security can only be considered lawful when the legal conditions are met and when they are proportionate. Therefore, a correct understanding of the concept of catalog offenses is of great importance both for the application of the fundamental principles of criminal procedure law and for the protection of individual rights.