Whether it was Sherlock Holmes, Hercule Poirot, Patrick Jane, Shawn Spencer, or even real-life heroes like Frank Serpico or Elliot Ness, something inspired you to search for information on how to become a detective. This inspiration could prove to be a great first step towards an exciting future! Whether you aim to build a career in law enforcement or set up your own private practice as a detective, this article will help you get a better understanding of what it takes to be a professional crime-solver.

Criminal investigation is a growing field. According to Data USA, there were over 140,000 detectives & criminal investigators solving crimes across the country in 2021. 

In this article, we’ll look at the typical paths toward careers as detectives and investigators–in law enforcement and beyond.

Whether in the public sector, upholding the law for the greater good, or in the private domain, solving specific cases in different areas, detectives share a common goal: seeking the truth and ensuring justice prevails. 

A detective is a skilled professional trained to uncover, analyze, and solve crimes. Their role is often portrayed in detective shows, movies, and novels, but the reality of their work often goes beyond the scripted drama. Detectives play a crucial role in the justice system, working to solve crime, in the many forms it exists. 

Based on the sector they work in, detectives can be classified into two broad categories: police or public detectives and private detectives.

police detective


Police Detectives or Public Detectives

Police detectives, also known as criminal investigators, are law enforcement professionals who specialize in investigating criminal cases. These dedicated individuals work within police departments, sheriff’s offices, or federal agencies, with the primary goal of solving crimes and ensuring public safety. Their roles are sometimes highly specific, investigating crimes such as arson, homicide, robbery, vandalism, fraud, burglary, and assault.

What Do Police Detectives Typically Do?

Though their specific roles may vary based on their agency or police department, most police detectives have the following responsibilities:

  • Investigation:
    Police detectives meticulously investigate crimes, which may range from homicides and robberies to white-collar offenses. They gather evidence, interview witnesses, and reconstruct the sequence of events to solve cases.

  • Collaboration:
    Working closely with forensic experts, fellow officers, and prosecutors, police detectives collaborate to build strong cases for court proceedings. Teamwork is often key to the success of their investigations.

  • Community Engagement:
    Establishing trust within the community is crucial. Detectives often engage with the public, addressing concerns, and fostering cooperation to enhance crime prevention efforts.

While the day-to-day reality of a police detective may also involve intense investigations and collaborative efforts, the portrayal of their work on detective shows often captures the essence of the challenges they face. From solving complex murders to navigating the intricacies of interpersonal relationships, these shows sometimes provide an exaggerated yet insightful glimpse into the life of a public detective.

private detective

Private Detectives

Private detectives, also known as private investigators (PIs), are hired by individuals, businesses, or attorneys to conduct investigations, often of a more personal or specialized nature. They operate independently from federal and state law enforcement agencies but may sometimes be consulted by police departments for specific investigations. 

What Do Private Detectives Typically Do?

While their scope of work may differ based on the clients and cases they’re hired for, private detectives typically perform the following tasks:

  • Surveillance:
    Private detectives may conduct surveillance to gather information on individuals, uncovering activities relevant to cases.
  • Background Checks:
    Performing comprehensive background checks is a common task. Private detectives may look into an individual’s history to verify credentials, uncover potential criminal records, or assess financial situations.
  • Legal Support:
    Private detectives may assist in legal matters by collecting evidence, locating witnesses, or providing insights that contribute to a client’s legal strategy.

Detective shows featuring private investigators, like ‘The Mentalist’ or ‘Psych,’ do capture some truth, but tend to be dramatized greatly. The risks involved, effort required, and skills needed are often common in both fiction and reality. 

Whether donning the badge of a public detective or operating independently as a private investigator, these individuals share a commitment to uncovering the truth and ensuring that justice is served. 

To become a police detective in the United States, the path typically involves gaining law enforcement experience and meeting specific educational and training requirements. 

Here are the common steps to becoming a police detective:

1) Education

To become a police detective or public detective in most states, you must have at least a high school diploma or equivalent. Some federal agencies and police departments may require you to have completed college coursework or a college degree

Federal agencies such as the Federal Bureau of Investigation (FBI) may require a bachelor’s degree in a relevant field. 

What degrees can help you become a detective?

The journey to becoming a detective often begins with a solid educational foundation, laying the groundwork for the critical thinking and analytical skills essential for investigative roles. Certain fields of study can significantly contribute to your preparation and success as a public detective.

Here are some fields of study that can better prepare you for the role:

  • Criminology

A degree in criminology provides a comprehensive understanding of criminal behavior, the justice system, and the societal factors influencing crime. It can equip aspiring detectives with valuable insights into the complexities of the criminal landscape.

  • Criminal Justice

A degree in criminal justice (CJ) offers a broad overview of the legal system, law enforcement procedures, and criminal behavior. This foundational knowledge is particularly relevant for individuals aiming to transition into investigative roles. It’s fairly common to land law enforcement jobs with a criminal justice degree, which makes it a popular major.

  • Forensic Science or Criminalistics

For those interested in the scientific aspects of investigation, a degree in forensic science explores scientific methods of solving crimes. This includes understanding evidence collection, analysis, and forensic technologies. A degree in biology, chemistry, or physics could also help if you want a career in forensic science.

Related: Criminology vs. Criminal Justice vs. Criminalistics: Explained

  • Law Enforcement

Some institutions offer specific degrees in law enforcement, providing specialized training in police procedures, ethics, and community policing. This targeted education can be advantageous for those with a clear goal of entering the law enforcement field.

  • Psychology

The study of psychology can be instrumental in investigative work, particularly when dealing with understanding motives, behavior patterns, and psychological aspects of criminal cases. A background in psychology enhances the ability to analyze and interpret human behavior.

  • Computer Science or Cybersecurity

In the digital age, crimes involving technology are on the rise. Degrees in computer science or cybersecurity equip detectives with the skills needed to navigate the complexities of cybercrime investigations.

  • Political Science

Degree programs in political science can offer a broader perspective on the legal and political aspects of criminal justice. This knowledge is valuable for detectives dealing with cases that intersect with legal and political landscapes.

  • Public Administration

Understanding the administrative and organizational aspects of law enforcement is crucial for those aspiring to leadership roles within investigative units. A degree in public administration provides insights into the management of law enforcement agencies.

  • Specialized Certifications and Further Education

Beyond degrees, consider earning specialized certifications in areas relevant to your investigative interests, such as fraud examination, digital forensics, or crime scene analysis. Further, given the evolving nature of investigative techniques and technologies, consider pursuing ongoing education to stay up-to-date in the field.

A question students often ask is, “Can I become a detective without a college degree?”
The answer is, yes, it is possible to become a detective without a degree, but the path may vary depending on law enforcement agencies and their specific requirements. While many agencies prefer candidates with a college degree, some law enforcement agencies may accept a combination of work experience, training, and relevant certifications in lieu of a degree.

Gaining law enforcement experience, specialized training, professional certifications, military service, and showcasing relevant skills and accomplishments in the field could help you become a detective even if you don’t have a degree.

While these programs offer valuable foundations, specialized training and skills are equally important in shaping a successful investigative career. The combination of education and hands-on experience creates a well-rounded skill set, preparing you to be a better public detective.

2) Experience and Specialized Training 

To become a detective, you usually need to first gain experience as a law enforcement officer, often by attending a police academy and becoming a police officer. For certain roles, you may also need to develop investigative skills through various specialties such as homicide, fraud, financial crime, surveillance, computer crime, etc. Developing skills in data analysis, visualization, storytelling, communication, investigative reporting techniques, and other relevant areas will be super useful as you progress.

According to Police1, while the duration can vary depending on factors like location and agency type, in 2018, the average length of a US police academy program was 833 hours (which can take around five months to complete), as reported by the Office of Justice Programs. In some states and local departments, this duration may vary significantly. 

Becoming a public detective without first becoming a police officer is less common, as many law enforcement agencies typically require individuals to gain experience as police officers before transitioning to detective roles. However, there are some exceptions, and certain specialized roles within law enforcement agencies may have different entry requirements. It’s advisable to research specific agency policies and requirements, as well as explore alternative paths such as obtaining relevant degrees, certifications, or experience in related fields that may be considered for detective positions within agencies.

3) Promotions and Examinations

To become a public or police detective, you will likely have to work towards promotions. This usually requires gaining relevant experience or demonstrating reliability. Gaining experience in an investigative unit can help bolster your chances of securing a promotion or eligibility for detective examinations.

Ensure you pass health and fitness exams, background checks, polygraph tests, drug screenings, physical exams, medical exams, and psychological exams. To achieve this, you need to maintain physical and mental health. This means eating well, sleeping on time, and staying active. 

To be eligible for detective examinations and promotions, in most cases, you will need about 3-5 years of relevant experience in law enforcement or criminal investigations. This can vary greatly based on location, agency, and the specific detective job you’re aiming for. Some states and agencies may also have specific criteria for becoming a detective, such as minimum college credits and GPA requirements. It’s best to invest time researching the roles you want before planning your path towards becoming a detective. 

In some agencies, if a position involves access to sensitive or confidential information, applicants must obtain a government security clearance. Most security clearances require additional checks that may include interviews with spouses, neighbors, friends, family, and work colleagues.

To read more about how to become a police officer or detective, check out the official Occupational Outlook Handbook for the role, published by the US Bureau of Labor Services (BLS).

Becoming a private detective or investigator is a dynamic journey that often starts with a foundation in law enforcement. If you’ve gained experience as a police detective and are considering transitioning to the private sector, or if you’re looking for ways to establish a reputable practice as a PI, here’s a roadmap to guide you through this interesting path:

1) Pursue Relevant Education

In most cases, you can become a private detective with just a high school diploma or GED. However, higher education in criminal justice and related areas can open doors. A college degree can also boost your credibility, which in turn can help you get more clients.

2) Earn Relevant Experience

While a college degree in criminal justice or a related field can enhance your qualifications, practical experience is equally crucial. Building a strong foundation as a police detective, and volunteering to assist with investigations when possible can equip you with investigative skills that form the bedrock of a successful PI career. Consider pursuing apprenticeships with seasoned investigators. If you’re lucky, your local sheriff might be able to spare time to provide valuable insights. Some police departments also offer training programs for high school and college students. If you already have experience in the military, police department, or similar, the process of becoming a PI can be a lot easier. 

3) Meet Licensing Requirements

Licensing requirements for private investigators vary by state. In most states, private investigators must be licensed. Familiarize yourself with the specific requirements in your state. This may include passing an exam, meeting minimum experience thresholds, and submitting to background checks.

3) Consider Specializing Your Skills

Identify your areas of specialization within private investigation. Whether it’s surveillance, fraud detection, or cybersecurity, honing specialized skills can set you apart and cater to specific client needs. (A great way to start is by identifying the most common crimes in your community).

4) Invest in Technology

Embrace technology to enhance your investigative capabilities. Stay updated on the latest tools and software that can aid in data analysis, surveillance, and information gathering. 

5) Market Your Services

Develop a strong online presence and marketing strategy to attract clients. Utilize social media, a professional website, and other platforms to showcase your expertise and services. Leveraging your existing network and making yourself visible in your local community are great ways to start establishing your career as a private detective. 

Whether you’re looking to start as a private detective, or are transitioning from a police detective to a private investigator, a strategic approach to education and networking can help you build a credible practice. 

To read more about how to become a private detective, check out the official Occupational Outlook Handbook for the role, published by the US Bureau of Labor Services (BLS).

There’s a lot more to consider when pursuing investigative careers. Let’s explore the various detective jobs that exist today.


Besides the broad sectoral categorization (public and private), detectives may play super-specific roles across the law enforcement and criminal justice landscape. Today, there are many different types of detectives, focusing on distinct forms of criminal activity.

Here are some of these specialized roles, and the responsibilities that accompany them:

Homicide Detectives

Specializing in investigating murders and other violent deaths, homicide detectives work to uncover the circumstances surrounding loss of life. Homicide detectives usually work in law enforcement agencies, but private detectives are sometimes consulted or hired for homicide investigations.
(Harry Bosch from ‘Bosch’ is a good fictional reference on what a homicide detective career might look like).

Cybercrime Detectives

With the increasing prevalence of digital offenses, cybercrime detectives focus on investigating felonies that occur in the online realm, such as hacking, identity theft, and online fraud. Becoming a cybercrime detective may require additional training in cybersecurity, computer systems, or related areas. You may also need to earn credentials like the National Initiative for Cybersecurity Careers And Studies (NICCS)’s Certified Professional Criminal Investigator (CPCI).
(Think Penelope Garcia from ‘Criminal Minds’). 

Related: How to Become a Cybersecurity Specialist? 

Special Victims Unit (SVU) Detectives

Handling cases involving vulnerable populations, SVU detectives investigate crimes like domestic violence, child abuse, sex crimes, and crimes against the elderly, working to protect those who may be particularly at risk.
(Think Olivia Benson from ‘Law & Order: Special Victims Unit’).

Narcotics Detectives

Tasked with combating drug-related crimes, narcotics detectives investigate and apprehend individuals involved in the illegal drug trade, addressing issues related to drug trafficking and abuse. They typically work for organizations like the Drug Enforcement Administration (DEA), police departments, or other federal and state agencies. 

(Think Kima Greggs from ‘The Wire’ or Stephen Murphy from ‘Narcos’–and real life!).

Missing Persons Detectives

Dedicated to locating individuals who have disappeared, missing persons detectives work closely with families, gather information, and coordinate search efforts to find and ensure the safety of the missing person/people. Private investigators are often hired to investigate missing persons. In many states, missing persons detectives handle cases through systems such as ‘Silver Alerts,’ to help find seniors, children, and other individuals who have been reported as “missing”.
(Think Jack Malone from ‘Without a Trace’).

Robbery Detectives

Focused on crimes involving theft by force or threat, robbery detectives investigate incidents such as armed robberies and burglaries, aiming to identify and apprehend suspects involved in these crimes. Some police departments may have combined divisions for certain crime groups, often solving robberies along with homicide or gang-related crimes.
For example: The Los Angeles Police Department (LAPD) has a Robbery-Homicide Division (RHD) focused on investigating crimes of both natures.

Cold Case Detectives

Assigned to unsolved cases that have gone cold, these investigators revisit older investigations with fresh perspectives. They use new technologies and investigative techniques to try and solve cases that have remained unresolved for an extended period. They aim to bring closure to those affected by past crimes and serve justice. The National Institute of Justice (NIJ) recognizes the importance of cold case investigation. As such, efforts are actively taken to apply modern investigation methods to solve cold cases. Besides government bodies, private organizations such as Uncovered also aim to build technology to solve cold cases nationwide.

Gang Detectives

Focused on combating gang-related criminal activities, gang detectives gather intelligence on gang members, investigate gang-related violence, and work to disrupt criminal enterprises associated with gangs. The FBI has nationwide Violent Gang Task Forces through which multiple federal, state, and local law enforcement agencies collaboratively address the violent gang crime plaguing communities.

White-Collar Crime Detectives

White-collar crime detectives focus on investigating non-violent, financially motivated crimes committed by individuals, businesses, or government professionals, such as corporate fraud and insider trading. The Federal Bureau of Investigation (FBI) has dedicated teams focusing on white-collar crime. The US Securities and Exchange Commission (SEC) has an Enforcement Division that investigates white-collar criminal activities. If you’re interested in solving white-collar crime, consider looking into career paths at the Commodity Futures Trading Commission (CFTC), which includes roles such as futures trading investigators and specialists. Other agencies and some state departments may also have detectives who specialize in this area. Private investigators can also build strong careers as claims investigators or financial crimes detectives, investigating insurance claims, embezzlement, etc. 

Related: Finance Degrees: All You Need to Know  

Public Defender Investigators and Other Legal Investigators

Public defender investigators play a unique role in the criminal justice system. They usually work alongside public defenders to ensure that individuals accused of crimes receive fair and effective representation. Their primary responsibility is gathering information and evidence that can be used to build a strong defense for the accused. Becoming a legal investigator may require specific education in legal studies. It may also require earning certifications through programs such as the National Association of Legal Investigators (NALI)’s Certified Legal Investigators program

Arson Investigators

Trained to determine the cause and origin of fires, arson investigators work to uncover whether a fire was intentionally set and gather evidence for potential criminal charges. They often work closely with local fire departments or insurance companies.

These are just a few examples of the investigative careers you can pursue today. Detectives often specialize further based on the needs of their respective law enforcement or investigative agencies. The diversity of detective roles reflects the complexity of the criminal justice system and the need for specialized skills in various areas of investigation. 

While the pathways toward becoming a detective are fairly clear, this career demands a unique blend of skills, dedication, and a passion for uncovering the truth.

If you want to become a detective, whether in the public sector championing the cause of justice, or as a private investigator navigating the intricacies of individual cases, the road ahead is both challenging and rewarding. The foundation begins with education–a solid understanding of criminal justice principles, investigative techniques, and ethical considerations in criminal justice.

You could also aim for specialized investigative roles. Cybersecurity, chemistry, finance, and IT are some degrees that can prepare you for these specialized detective roles. It all depends on where your passion lies. Research the roles you want, and find degree programs that can help you get them. (Our free college match tool can help with the latter!).

It’s equally important to gain practical experience, whether through internships, entry-level positions in law enforcement, or apprenticeships with seasoned investigators. This hands-on experience will not only hone investigative skills but also provide invaluable insights into the realities of the profession.

The importance of effective communication, attention to detail, and critical thinking cannot be overstated. Detectives must be adept at navigating complex situations, collaborating with diverse teams, and drawing connections that may elude others. These skills, coupled with a commitment to upholding the law and serving the community, form the bedrock of a successful detective career.

In the dynamic area of criminal investigation, adaptability is key. Technology evolves, investigative techniques advance and the nature of crimes continually transforms. A detective must stay current with these changes, embracing lifelong learning to stay at the forefront of their field.

As you plan your path towards a detective career, remember that the journey is as significant as the destination. Each step, and each experience, contributes to your success as a skilled investigator. Whether you find inspiration in the fictional exploits of beloved TV detectives or draw motivation from the real-life heroes who have shaped the field, the essence remains the same–the pursuit of truth and justice.

The world awaits the next generation of detectives, ready to unravel the mysteries that lie ahead. 

Is there a specific age limit to becoming a detective?

Age requirements for becoming a detective may vary by jurisdiction and agency. While there is typically no upper age limit, most agencies require candidates to be at least 21 years old and meet other eligibility criteria.

Can I become a detective with a background in a different field?

It’s possible. Many detectives enter the field with diverse educational and professional backgrounds. However, having a degree or relevant experience in criminal justice, forensic science, psychology, or related fields can enhance your candidacy. You could also aim for certain specialized detective roles by earning degrees relevant to those fields. For instance, you can become a white-collar crime investigator with a degree in finance or accounting. Identify the role you want, and find a degree that can prepare you for it. Our free college match tool can help with the latter.

How long does it take to become a detective?

The time it takes to become a detective will vary depending on the type of detective you want to be and the agency you want to work for. 

Generally, becoming a public or police detective requires first becoming a police officer. This usually requires graduating from high school and joining the academy. Earning an associate or bachelor’s degree in psychology, criminal justice, criminology, or related areas is usually preferred by most agencies, though not always a hard requirement. Police academy programs generally last six to eight months, after which officers must typically gain four or five years of experience before they can take a promotional exam to become a detective. Some police departments allow officers to substitute a college degree for a year of experience. Overall, it can take anywhere from five to eight years to be promoted from a police officer to a detective.

On the other hand, becoming a private detective usually does not have specific education requirements, but may often require previous experience in criminal justice or related areas.