Detectives and Criminal Investigators

Core Tasks

1. Check victims for signs of life, such as breathing and pulse.
2. Obtain facts or statements from complainants, witnesses, and accused persons and record interviews, using recording device.
3. Secure deceased body and obtain evidence from it, preventing bystanders from tampering with it prior to medical examiner's arrival.
4. Record progress of investigation, maintain informational files on suspects, and submit reports to commanding officer or magistrate to authorize warrants.
5. Prepare reports that detail investigation findings.
6. Prepare charges or responses to charges, or information for court cases, according to formalized procedures.
7. Preserve, process, and analyze items of evidence obtained from crime scenes and suspects, placing them in proper containers and destroying evidence no longer needed.
8. Obtain summary of incident from officer in charge at crime scene, taking care to avoid disturbing evidence.
9. Note, mark, and photograph location of objects found, such as footprints, tire tracks, bullets and bloodstains, and take measurements of the scene.
10. Examine records and governmental agency files to find identifying data about suspects.
11. Secure persons at scene, keeping witnesses from conversing or leaving the scene before investigators arrive.
12. Provide information to lab personnel concerning the source of an item of evidence and tests to be performed.
13. Analyze completed police reports to determine what additional information and investigative work is needed.
14. Examine records to locate links in chains of evidence or information.
15. Search for and collect evidence, such as fingerprints, using investigative equipment.
16. Prepare and serve search and arrest warrants.
17. Question individuals or observe persons and establishments to confirm information given to patrol officers.
18. Determine scope, timing, and direction of investigations.
19. Obtain and verify evidence by interviewing and observing suspects and witnesses or by analyzing records.
20. Participate or assist in raids and arrests.
21. Organize scene search, assigning specific tasks and areas of search to individual officers and obtaining adequate lighting as necessary.
22. Summon medical help for injured individuals and alert medical personnel to take statements from them.
23. Notify command of situation and request assistance.
24. Block or rope off scene and check perimeter to ensure that entire scene is secured.
25. Identify case issues and evidence needed, based on analysis of charges, complaints, or allegations of law violations.
26. Notify, or request notification of, medical examiner or district attorney representative.
27. Collaborate with other offices and agencies to exchange information and coordinate activities.
28. Maintain surveillance of establishments to obtain identifying information on suspects.
29. Testify before grand juries concerning criminal activity investigations.
30. Perform undercover assignments and maintain surveillance, including monitoring authorized wiretaps.

Technology & Tools

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