District Attorney Investigator I (#RL3021)
$41.68-$50.66 Hourly / $7,224.22-$8,781.08 Monthly / $86,690.65-$105,373.03 Yearly


Under general supervision, investigates alleged and suspected violations of criminal and civil law falling within the jurisdiction of the District Attorney’s Office; makes recommendations for actions to be taken; and does related or other work as required in accordance with Rule 3, Section 3 of the Civil Service Rules.


This is the entry level District Attorney Investigator. Initially, employees are assigned the less difficult investigations and work is closely reviewed and supervised; but as knowledge and experience are gained, employees are expected to work more independently. Work may involve an element of personal danger and may entail long hours of work at unusual times of the day or night.

Employees of the District Attorney Investigator series are statutory full-time peace officers and have a duty to act upon criminal violations occurring in their presence. Employees are peace officers as defined by Section 830.1 of the Penal Code.


  • Conducts investigations of civil and criminal matters such as consumer and welfare fraud, misconduct of public officials, homicides, embezzlement, suspected violations of corporate security laws and mental health matters; conducts investigations requested by the Grand Jury; and investigates failure to provide cases.
  • Interviews and questions accused or suspected individuals and witnesses; examines court, police, public and governmental records needed for investigations; records and evaluates information obtained.
  • Inspects crime scenes to locate, identify, assemble, preserve, record and evaluate information.
  • Establishes and maintains contact with informants; gathers intelligence information concerning alleged criminal activities.
  • Assembles and prepares evidence for presentation in court; assists attorneys in court; gives testimony in court.
  • Analyzes and evaluates the results of investigations in light of recent court decisions; reviews reports of other law enforcement agencies to determine if all investigative avenues have been explored; detects defenses which may have been overlooked.
  • Makes oral and written reports.
  • Serves legal papers such as subpoenas, warrants and summonses; serves and executes extradition papers.
  • Assists in coordinating the investigative activities of the District Attorney’s Office with local, state and federal law enforcement agencies.
  • Develops and maintains positive relations with the public to gain compliance and trust; fosters collaborative partnerships with community members and organizations.
  • Negotiates and arranges for repayment of fraudulently obtained funds.
  • As assigned, acts in mutual aid situations which may include active law enforcement duties; applies proper techniques of arrest; determines appropriate course of action when faced with potentially violent situations; works in an undercover capacity.


Experience: Three years of experience as a peace officer in a public law enforcement agency including demonstrated experience in felony investigations.

Substitution: Completion of 60 semester units in police science, criminology, sociology, psychology, or closely related curriculum may be substituted for the required general law enforcement experience on a year-for-year basis to a maximum of two years.

License: Possession of a valid California driver’s license.

Certificates: Possession of an Intermediate P.O.S.T. Certificate (or proof of eligibility for such certificate) including or supplemented by successful completion of approved courses in Powers of Arrest and use of firearms in accordance with Penal Code Section 832.  Such courses must have been approved by the California Commission on Peace Officers Standards.

Meet and maintain minimum standards required for peace officers as set forth in Sections 1029 and 1031 of the California Government Code. 


Techniques, methods, and procedures used in crime detection and criminal investigations; community-based policing and collaborative problem solving between community residents and law enforcement; rules of evidence, arrest and court procedures; interviewing techniques and procedures; civil and criminal laws and ordinances in effect in the County; techniques of securing, evaluating, and preparing legal rights of citizens; firearms safety.


Gather, assemble, analyze, and evaluate facts and evidence; interpret and fairly and equitably apply legal provisions; obtain information through questioning and observation; draw logical conclusions and make proper recommendations; analyze situations and adopt effective courses of action; prepares comprehensive reports on investigations; learn to operate specialized investigative equipment; express oneself clearly and concisely, both orally and in writing; establish and maintain effective working relationships with other investigators, law enforcement officials, the public and others.

San Joaquin County complies with the Americans with Disabilities Act (ADA) and, upon request, will consider reasonable accommodations to enable individuals with disabilities to perform essential job functions.

CLASS: RL3021; EST: 6/8/1988; REV: 11/30/2022;