How to Become a Criminal Investigator in California

According to the California Department of Justice, as of 2009, there were 122,042 sworn law enforcement officers in California, which included 55,649 officers working in city police departments and 51,612 officers working in county sheriff’s offices.

This major U.S. state reported 160,629 violent crimes committed in California in 2012, which included:

  • Homicides: 1,878
  • Forcible rapes: 7,828
  • Robberies: 56,491
  • Aggravated assaults: 94,432

With much of the crime concentrated in the metropolitan areas of Los Angeles, San Jose, San Diego, and San Francisco, and a total state population of more than 38 million, detectives and other criminal investigators working at the state, city, and county levels in California work diligently to bring resolution to unsolved crimes.

Becoming a Detective with the California Bureau of Investigation

California Office of the Attorney General, California Bureau of Investigation

The California Bureau of Investigation (CBI), within the Office of the Attorney General, provides investigative services to assist criminal investigations at the local, state, and federal level in California. The specialized services provided by the CBI include:

  • Criminal profiling
  • Polygraph examinations
  • Sexual predator tracking
  • High-technology crime investigation
  • Violent crimes investigation

Headquartered in Sacramento, the CBI extends its criminal investigation/law enforcement services to all 58 counties in California. The major programs of the CBI include:

  • California Witness Protection Program
  • Department of Conservation Program
  • Foreign Prosecution Program
  • Investigative Support Team Program
  • Major Crimes Program
  • Polygraph Unit
  • Sexual Assault Felony Enforcement
  • Sexual Predator Apprehension Team
  • Unsolved Violent Crime Program
  • Violent Crimes Profiling Program

Individuals who want to become a special agent criminal investigator with the CBI must qualify in one of three ways:

  • Serve as a Special Agent trainee with the Department of Justice for at least one year
  • Possess at least two years of experience as a peace officer in an investigative assignment, along with at least two years of college (60 semester units) study
  • Possess at least one year of experience as a peace officer in an investigative assignment, along with a bachelor’s degree

Just some of the majors that support a career in criminal investigations include:

  • Criminology
  • Sociology
  • Psychology
  • Police science
  • Justice administration

Qualifying to Become a Detective in California’s Major Cities

Los Angeles Police Department, Criminal Investigation Division

The Los Angeles Police Department, Criminal Investigation Division is divided into three investigative units, each of which is led by an Officer in Charge (Lieutenant II), an Assistant Officer in Charge (Detective III), and a number of investigators (Sergeants II and Detectives II).

Individuals who want to become detectives with the Los Angeles Police Department must first become police officers with the Department.

The first promotion available to police officers is a detective within the investigation branch.

Individuals who want to become sergeants within the Investigation Division must have at least four years of experience as a detective.

San Francisco Police Department, Investigation Division

The Investigation Division within the San Francisco Police Department consists of three units:

  • Major Crimes Unit
  • Special Victims Unit
  • Special Investigations Division
    • Homicide
    • Robbery
    • Gang Task Force
    • Auto
    • Burglary
    • Fencing
    • Fraud
    • Financial elder abuse
    • Hit and run
    • Neighborhood investigation
    • Sexual assault

To become a criminal investigator with the San Francisco Police Department, individuals must have at least two years of experience as a sworn member of the San Francisco Police Department.

San Diego Police Department

Criminal investigations for the San Diego Police Department are organized into a number of teams:

  • Cold Case Homicide Unit
  • Vice Operations
  • Sex Crimes
  • Special Investigations
  • Metro Arson Strike Team
  • Homicide
  • Gangs
  • Domestic Violence Unit
  • Elder and Dependence Abuse
  • Child Abuse
  • Auto Theft Unit

Individuals who want to become detectives with the San Diego Police Department must first serve as San Diego police officers. All new officers must begin their careers in the patrol division.

After four years of experience, officers may apply for an investigative position. The Department notes that a college degree at the associate’s or bachelor’s levels are often helpful when obtaining an investigative position.

Typical degree majors applicable to criminal investigations include:

  • Criminal justice
  • Criminology
  • Justice administration
  • Public administration
  • Psychology

San Jose Police Department, Bureau of Investigations

The Bureau of Investigations within the San Jose Police Department is structured as follows:

  • Investigations I
    • Homicide/Crime Scene
    • Gang Investigations/Assaults/Graffiti
    • Sexual Assaults
    • Megan’s Law/290 Unit
    • CED-ICAC
    • Human Trafficking
    • Court Liaison
    • Family Violence
    • Robbery
  • Investigations II
    • Robbery/Warrants/Juvenile/Missing
    • Convert Response Unit
    • Financial Crimes
    • RATTF
    • Communications

Candidates for criminal investigation jobs with the San Jose Police Department must first become police officers with the Department.

To qualify as a candidate for a police officer job, candidates must be at least 21 years old and must possess at least 40 semester college credits (60 quarter college credits) from an accredited college or university.

Common college degree programs for candidates may include:

  • Sociology
  • Psychology
  • Forensic psychology
  • Criminal justice
  • Criminology

Detectives with the San Jose Police Department are sergeants, which requires at least three years of experience as a San Jose police officer.

Other large municipal criminal investigations teams found throughout California include:

  • Fresno Police Department, Investigations Division
  • Long Beach Police Department, Investigations Bureau (Detective Division, Gang and Violent Crimes Division, and Forensic Science Services Division)
  • Oakland Police Department, Criminal Investigation Division
  • Bakersfield Police Department, Investigations Division
  • Anaheim Police Department, Investigations Division

California’s Criminal Investigation Departments at the County Level

Criminal investigations also take place at the county level in California through sheriff’s departments. Some of the largest criminal investigation operations among county sheriff’s offices in California include:

Los Angeles County: The Los Angeles County Sheriff’s Department has a Detective Division, which includes the following units:

  • Fraud and Cyber Crimes Bureau
  • Homicide Bureau
  • Major Crimes Bureau
  • Narcotics Bureau
  • Operation Safe Streets Bureau
  • Special Victims Bureau
  • Task Force for Regional Auto Theft Prevention

San Diego County: The San Diego County Sheriff’s Department has a Special Investigations Division, which includes investigative work through the following units/teams:

  • Criminal intelligence
  • Fugitive task force
  • Gang suppression unit
  • Narcotics task forces
  • Regional gang task forces

Orange County: The Orange County Sheriff’s Department has an Investigations Division that is organized into two units: Criminal Investigations and Special Investigations.

Back to Top