What Missing Person Investigations Involve
A missing person investigation begins when someone disappears under unexplained or concerning circumstances. Police focus on finding the person alive and returning them safely to their family. Investigators interview family and friends, check hospitals and shelters, review phone records and credit card usage, and may issue public alerts with photos. Time is critical in these cases, especially when children or vulnerable adults are involved.
What Homicide Investigations Involve
A homicide investigation starts when a person's death is determined to be caused by another person's unlawful actions. Police work to identify how the person died, gather physical evidence from the crime scene, determine a timeline of events, and identify suspects. Investigators collect DNA samples, fingerprints, witness statements, and other forensic evidence to build a case for prosecution in court.
Key Differences in Approach
Missing person investigations prioritize speed and prevention of harm, often involving immediate search efforts and public appeals. Homicide investigations are more methodical and long-term, focusing on building a legal case against a suspect. Missing person cases may involve searches of wilderness areas, water, and buildings, while homicide cases center on crime scene analysis and suspect investigation. The skills and tools used in each type of investigation are also different.
When Cases Overlap
If a missing person is later discovered dead, the investigation often transitions from a missing person case to a homicide investigation. Police must determine whether the death was a homicide or accident. If homicide is determined, the investigation shifts focus to finding the responsible party. Many active missing person cases have a homicide component investigated simultaneously if foul play is suspected from the beginning.
Agencies Involved
Local police departments typically lead missing person investigations, sometimes with help from state police and federal agencies like the FBI for high-profile cases. Homicide investigations are usually handled by a homicide detective division within a police department, often with support from medical examiners, forensic specialists, and prosecutors. 
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