how to become a crime scene investigator

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Introduction to crime scene investigation

Over the last 20 years, popular culture has become enamored with procedural crime shows that highlight the investigatory process. Consequently, there has been considerable growth in the number of educational programs and career options available for those interested in pursing a position as a crime scene investigator.

While what is presented on television and in the movies may glamorize the position for entertainment purposes, a real world crime scene investigator (CSI) plays a crucial role within the judicial system. For anyone considering a career in crime scene investigation, being able to differentiate the role the CSI plays on television and the real-world responsibilities that make the position a vital part of society is essential.  

Specifically, CSIs gather and analyze evidence procured at a crime scene to aid those involved in the investigation process. This includes the gathering of fingerprints, footprints, blood splatter, hair, fibers, and any other physical evidence found at the scene. The CSI processes the evidence to determine if the material can help in solving the case. Outside of evidence retrieval and analysis, they also play an important role in presenting their findings in court, if needed. As such, the CSI must be as accurate and detailed as possible considering their role in either bringing a criminal to justice or in proving an individual’s innocence.

Several specializations exist within crime scene investigation including photography, evidence collection, technician, artist, and evidence analyst.  Successful CSIs are able to take advantage of various aspects of the position that make the profession exciting and fulfilling. In fact, according to the U.S. Bureau of Labor and Statistics, the average CSI salary continues to rise , which is complemented by the predicted increase in available positions. Outside of the more tangible benefits, investigators can take pride in knowing they are part of a process that makes societies safer.

What do CSIs do?

The numerous roles CSIs play within the investigation process start immediately after a crime has been committed and can extend to court proceedings related to the case. Throughout this process, the roles of CSIs vary depending upon the setting. Typically, in larger cities, CSIs may solely work within a specific specialization, whereas in smaller communities, their role might be broader. Investigators can be involved throughout the entire process or specialize in specific areas of study that exist within crime scene investigation.

Upon arriving at a crime scene, CSIs focus on  the following 3 main areas:

Crime scene

  • Recognition

Initially, investigators survey the scene to determine the best methods to manage the area. They determine the size of the area and the extent of the crime. CSIs then establish what evidence needs to be collected and make sure important aspects of the scene have not been compromised. They also determine what equipment is required to document and collect the evidence and address any safety concerns that may arise.

  • Documentation

After surveying the scene, CSIs document both the physical scene and the evidence by marking areas that need further analysis. It’s crucial that their documentation is both comprehensive and accurate, as any mistake could negatively impact the case.

  • Collection

Once the investigators have documented everything about the crime scene, they are then able to start collecting the evidence that needs to be analyzed by forensic technicians. Proper care must be taken in the collection of the physical materials to avoid compromising the scene and evidence.


Depending on the size of the agency, CSI responsibilities may also include the analysis of the evidence. While larger agencies often restrict CSIs to working in the field, smaller agencies may need them to take on increased roles. Generally, CSIs focus their expertise on the field, while forensic scientists focus on analyzing the collected evidence. Within the laboratory, the evidence collected such as fingerprints, DNA, hair follicles is analyzed to determine what information can be acquired from the evidence to help the police and detectives in their investigations.


Typically, forensic scientists are the ones who are called into court as experts. CSIs in the field are only asked to court if there is an issue with the documentation and collection of evidence. Professionals who focus on the analysis of the evidence are expected to testify as experts if required. As such, those who have specialized knowledge in areas such as fingerprints, DNA, firearms, etc. are utilized as witnesses to explain the results of their analysis during court proceedings.

Tasks and duties

Below are a some of the specific tasks carried out by CSIs.

Lifting and collecting fingerprintsLocating and securing fingerprints at a crime scene

puzzle Collecting DNALocating and collecting DNA samples, such as blood, saliva, and hair

search Collecting trace evidence – Detecting and identifying materials that are often not visible             

alt"folder-remove-1" Examining weapons and trajectoriesAnalyzing a weapon and its ammunition; discovering the path of a bullet 

Testifying in courtProviding testimony in court with regard to the collection and analysis of evidence

What do I do to begin working: a step-by-step guide


Find an educational program that allows you to focus on various aspects of crime scene investigation. There are a variety of degree options that will provide the necessary academic background: criminal justice, forensic science, and natural sciences. Degrees can be earned at the associate’s, bachelor’s, and master’s level. The degree selection depends upon the role the student wishes to have within crime scene investigation.

Finding Employment

Since there are few law enforcement agencies that hire full-time CSIs, it is recommended to apply to become a police officer first. Most CSIs are officers who perform multiple duties, allowing them to gain investigatory experience within a police department. The ICSIA actually recommends that individuals who are looking to become a CSI have a well-rounded academic and professional experience, as the work is incredibly demanding, leading to CSIs not processing crime scenes for their entire career.


CSIs gain most of their experience and knowledge with on the job training. New investigators typically work under a seasoned CSI within a law enforcement agency prior to any independent work. New CSIs are provided with information and training on the documentation and evaluation of the area, processing the scene, and recording the physical space. Throughout their training, CSIs can also participate in programs offered by the International Association for Identification (IAI). Training programs include arson investigation, evidence photography, forensic anthropology, footwear and tire tread analysis.


Certification and licensing varies from state to state, but most takes place during the training process. Check with your state to determine any additional licensing or certification requirements. Outside of individual state requirements, CSIs can become certified through both the International Crime Scene Investigators Association (ICSIA), the American College of Forensic Examiners Institute (ACFEI), and IAI. Many employers look for certified CSIs as it showcases their high degree of knowledge and experience.

  • ACSIA: Crime Scene Investigator Certification with the ICSIA requires CSIs to have served at least 2 years working for a law enforcement agency. To earn the certification, candidates must complete 50 hours of post-secondary coursework and pass a written exam.
  • IAI: New CSIs can also become certified through the IAI in one of 4 areas: Certified Crime Scene Analyst, Certified Crim Scene Reconstructionist, Certified Crime Scene Investigator, and Certified Crime Scene Analyst. To earn certification from the IAI, CSIs must have at least one year of experience as well as 48 hours of instruction within 5 years of applying for certification.
  • ACFEI: This is an independent professional association that provides certification for CSIs who identify and handle evidence, conduct interviews, and testify in court.

Degrees and training required to work as a CSI

Associate’s degree

Associate programs typically provide a background in law enforcement and crime scene management while focusing on criminal justice overall. It is recommended that those who want to pursue employment as a CSI in more traditional settings continue to a more advanced degree.

The following coursework can be covered in an associate degree program:

Criminology – students explore the origins and patterns of crime

Quantitative methods in criminal justice – a course on recognizing crime causation

Critical analysis of the criminal justice system –  teaches students about crime reduction and safety methods

Criminal law – a course that identifies the functions of law enforcement, courts, and corrections

Criminal justice ethics: – students learn about ethical standards and conflict resolution


  • Can I complete the course online?
  • How long does this course take to complete?
    • 2 years
  • Does the course need to be accredited?
  • How long does it take to begin working after completing the course?
    • Individuals who have completed an associate’s CSI program can typically find entry-level employment upon completion of the program in the following areas:
      • Private investigator
      • Crime scene technician
      • Police officer

Bachelor’s degree

Bachelor programs provide an in-depth study of crime scene investigation, criminal investigations, and investigative techniques as well as increased opportunities for the practical application of skills learned in class.

Skills acquired through the following coursework include:

Criminalistics and forensics – Learn scientific techniques with regard to crime detection

Ballistics – Understand the effects of a fired weapon

Fingerprint evidence – Preserve and evaluate fingerprints

Trace evidence – how to evaluate and detect materials or substances found at a crime scene

Blood stain patterns – Interpretation of blood patterns


  • Can I complete the course online?
    • A bachelor’s degree in crime scene investigation can be earned online.
  • How long does this course take to complete?
    • 4 years
  • Does the course need to be accredited?
    • It is recommended that applicants chose a program that is accredited.
  • How long does it take to begin working as a CSI after completing the course?
    • Graduates can start working immediately after they have earned their degree. They will initially go through training in one of the following fields:
      • Crime scene photographer
      • Crime scene technician
      • Crime lab assistant
      • Fingerprint specialist

Master’s degree

Master’s programs for crime scene investigation do not exist. Therefore, those who want to earn an advanced degree typically study various forensic specializations that include anthropology, botany, DNA, odontology, and engineering.

The skills acquired in these master’s programs can include:

Forensic anthropology –  The skills to examine and process remains at a crime scene

Forensic odontology – Applying dental science to criminal investigations

Forensic botany – Study of plants and plant parts in the investigation of criminal cases

Forensic DNA – Analyze DNA found at a crime scene

Forensic engineering – Assess structural failures to determine liability


  • Can I complete the course online?
    • Online courses for a master’s degree are available.
  • How long does this course take to complete?
    • Earning a master’s degree in forensics typically takes 2 years. Applicants must have earned a bachelor’s degree prior to admission; therefore, it can take at least 6 total years of education.
  • Does the course need to be accredited?
    • Graduate programs in forensics should be accredited.
  • How long does it take to begin working after completing the course?
    • Given the fact that most graduates have experience prior to earning their master’s, employment can begin soon after finishing the program. Positions for graduates include the following:
      • Forensic science technician
      • Information security analyst
      • Criminal investigator

Salary and demand outlook for DEA agents

When looking at nominal salaries New York, California and Alaska are in the top 3 spots, but when the nominal salary is chosen then New York and California fall several places due to their notoriously high costs of living. Alaska moves into the top spot making it a great choice to live and work as a CSI. As with many other careers, the higher the level of education the more an individual can expect to earn. Individuals who hold a doctorate degree, on average, earn $20,000 more a year compared to those with a bachelor’s degree. 

Crime scene investigator salary information by state
future outlook tooltip icon

Payscale is a salary survey service meant to provide employers and employees with salary data at local levels to benchmark and compare. While Payscale has a much smaller sample size than BLS, Payscale does update more frequently so data may be considered fresher. Payscale also indicates salaries at a wider range of roles whereas BLS sometimes aggregates numerous professions into one category which may skew salary data. For this reason, we find Payscale to be a good secondary salary indicator. All information received from payscale is via a paid API. You can read more about payscale and their data methodology here.

Real salary
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The nominal salary is the unadjusted salary paid.

The real salary is adjusted to consider the purchasing power by state. We multiply the nominal salary by a state purchasing parities index to indicate the relative value of salaries by state. For instance, while New York or California might pay the highest nominal salary, these states are relatively expensive and so the real value of the salary is often less than a cheaper to live in state with a lower nominal salary.

Highest salary states


New York


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District of Columbia


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New Jersey


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Average salary

How experience affects earnings
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Payscale aggregates all employee salaries into experience and degree cohorts and charts out the average salaries accordingly. While this is interesting information, it is simply an indicator and should not be considered as a definitive accounting.

Bachelor's Degree

Timeline Salary
Less than 1 year $44,533
1 year $46,256
2 to 3 years $48,148
4 to 7 years $50,860
8 years or more $57,244

Did you know

The work completed by CSIs has historically played a critical role that led to the conviction of Ted Bundy, the Lindbergh kidnapper, Machine Gun Kelly, the BTK killer, and the Night Stalker.

What are the differences between a CSI, detective, and police officer?

Crime scene investigatorDocument, collect, and analyze evidence from a crime sceneLaw enforcement agencies -local and federalOn the job training working with veteran CSIsICSIA and/or IAI certification or licensingAssociate’s, bachelor’s, or master’s degree
DetectiveUtilizes information process by the CSI to solve a crimeLaw enforcement agencies - local and federalAttend a police academy; on the job training as a police officerWritten and physical examsCollege degree not required; associate’s or bachelor’s degree can help with advancement
Police officerFirst responders at a crime scene; manage scene until arrival of detectives and CSIsLaw enforcement agencies - localAttend a police academyWritten and physical examsCollege degree not required

Where do CSI's work?

IndustryEmployment (1)Percent of industry employmentHourly mean wageAnnual mean wage (2)
Local Government, excluding schools and hospitals (OEWS Designation)41,6300.77$ 37.08$ 77,120
Federal Executive Branch (OEWS Designation)41,2701.98$ 53.79$ 111,880
State Government, excluding schools and hospitals (OEWS Designation)22,1201.01$ 33.69$ 70,070
Postal Service (federal government)4800.08$ 50.15$ 104,300
Colleges, Universities, and Professional Schools3500.01$ 34.81$ 72,410

What tools and technologies do CSIs use?

  • Blood collection kit: provides the materials needed to collect blood from a crime scene
  • Excavation kit: used to uncover parts of a crime scene that may be hidden by natural materials
  • Trace evidence collection kit: used to collect trace materials such as hair, fibers, fabric, soil, etc.
  • Fingerprint kit: provides the materials needed to lift fingerprints from a crime scene
  • Trajectory kit: allows investigators to reconstruct the trajectory of bullets
  • Impression kit: provides everything needed to make dental impressions

Additional career progression

According to the ACSIA, those looking for a career in crime scene investigation should initially become employed as a police officer, since not many agencies have a full-time CSI on staff. As a police officer, it’s then possible to add additional responsibilities that allow for work investigating a crime scene.

Ultimately, CSI work can be quite demanding, which does lead to CSIs shifting their focus to other aspects of law enforcement to avoid burnout. The work of a CSI can be both strenuously physical and mentally taxing.  CSIs never know when they will be needed, as crime does not follow the 9-5 workday. According to former CSI Hayden Baldwin, it is best to limit a role as a crime scene investigator to between 7 and 10 years. Therefore, he suggests making sure individuals have a background that allows them to have professional mobility.

International Association for Bloodstain Pattern Analysts

An organization of forensic experts who specialize in bloodstain pattern analysis and promote education and training in this specialization.

International Association for Identification

The oldest and largest forensic association that provides information regarding certification and training as well as a yearly conference that offers lectures and hands-on workshops.

American Academy of Forensic Sciences

Professional membership organization that educates forensic scientists on the progression of forensics while helping in the development of policy.