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The County of DuPage
Wheaton, Illinois

Job Details for 2122 - EO Criminal Investigator

Job Description

GRADE: 111

Under general supervision; performs work of routine difficulty in criminal investigative work and in preparing reports regarding these investigations; performs related work as required.

This position involves investigating assigned criminal cases.  The work involves interviewing defendants to establish eligibility for Public Defender Services or collecting information for the State's Attorney's Office.  It also involves interviewing witnesses against the accused, accumulating documentary evidence in the case and investigating leads developed.  The work is performed under the general supervision of a Senior Criminal Investigator or other superior.  These positions are located in either the Public Defender's Office or the State's Attorney's Office.

The list of duties and responsibilities is illustrative only, and is not a comprehensive listing of all the duties and responsibilities performed by positions in this class.

• Interviews defendants assigned by the Court to be represented by the Public Defender's Office or State's Attorney's Office
• Prepares defendants' version of the alleged crime and the arrest for attorneys
• Interviews and investigates potential witnesses (prosecution and defense) who may be involved in the cases
• Takes photographs, has them processed and prepared for use as ordered by attorneys' locates witnesses and serves subpoenas as directed by attorney of record
• Testifies in court as required; transports witnesses, defendants and evidence to and from court proceedings as directed by attorneys.
• Maintains regular attendance and punctuality

• Adjusts work assignments and schedules in the event of an emergency to participate in emergency preparedness, response, and recovery activities as assigned.
• Depending on assignment may maintain required emergency management training, licensure and/or certifications.
• Performs related duties as required or assigned within job classification.

To perform this job successfully, an individual must be able to perform each essential duty satisfactorily. The requirements listed below are representative of the knowledge, skill, and /or ability required. Reasonable accommodations may be made to enable individuals with disabilities to perform essential functions.

Knowledge of:
• Laws and ordinances relating to arrest and search and seizure
• Rules of legal evidence
• General procedures used by grand juries in conducting criminal investigations and by courts in conducting criminal trials
• Geography of DuPage County
• Current office practices, procedures and equipment
• County policies and procedures
• Applicable federal, state, and local laws, rules, regulations, codes, and/or statutes

Skill in:
• Gathering a variety of information through interviews and interrogation
• Assisting in the preparation of cases for court or grand jury hearings.
• Using computer hardware and software including word processing, spreadsheets, databases, email, etc
• Applying an acquired knowledge of procedures, rules, regulations and services applicable to the assigned office

Ability to:
• Manage projects and multiple priorities simultaneously
• Establish and maintain effective working relationships with department and division staff, other departments and others, such as vendors
• Communicate and use interpersonal skills to interact with coworkers, supervisor, the general public, etc. to sufficiently exchange or convey information and to receive work direction
• Ensure compliance with applicable federal, state, and local laws, rules, and regulations and statutory requirements
• Convey excellent oral and written communication
• Work effectively under stress
• Maintain confidentiality


Completion of a High School Diploma or General Equivalency Diploma equivalent; Two years experience in criminal investigative or law enforcement work or, an equivalent combination of education and experience sufficient to successfully perform the essential duties of the job such as those listed above.

The physical demands described here are representative of those that must be met by an employee to successfully perform the essential functions of the job. Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions.

Medium Work: Exerting up to 50 pounds of force occasionally, and/or up to 25 pounds of force frequently, and/or up to 10 pounds of force constantly to move objects. While performing the duties of this job, the employee is frequently required to stand; walk; sit; use hands to finger, handle, or feel; reach with hands and arms; and talk; and/or hear. The employee is occasionally required to climb or balance; stoop; kneel; crouch; or crawl; and taste; or smell. Specific vision abilities required by this job include close vision, distance vision, color vision, peripheral vision, depth perception, and ability to adjust focus. The employee is required to maintain a level of physical fitness to meet department standards. Depending on assignment may need correct visual acuity to 20/20.

The work environment characteristics described here are representative of those an employee encounters while performing the essential functions of this job. Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions.

The work will occur in an office and field environment. While performing the duties and responsibilities the employee maybe exposed to loud noise, noxious odors, unsanitary conditions, chemicals, electricity, moving mechanical parts, varying weather conditions, explosives, and other related conditions and situations. Position is subject to atmospheric conditions: Fumes, odors, dust, mists, gases or poor ventilation.

Depending on assignment must possess and maintain in good standing a valid Illinois Drivers License.