Cold Case Investigations
What is a Cold Case?
Cold case investigations reexamine a missing persons disappearance after early leads have stalled or gone unanswered. These cases focus on reviewing records, timelines, and evidence with fresh perspective and updated methods. Investigators may revisit witness statements, analyze old data in new ways, or apply modern technology that was not available at the time. Progress often comes from careful attention to overlooked details rather than speed.
The objective is to uncover new information that can move the case forward and bring clarity to long-standing questions.
Our Cold Case Investigation Process
When resources or leads have been exhausted in a non-criminal missing persons case, law enforcement may no longer actively engage in the search. In cases such as this, Known Stranger Investigations will seek approval from law enforcement to begin working on the case and perform the following services:
Conduct telephone or physical interviews with family members, friends, neighbors, and co-workers of the Missing Person.
Create and disseminate posters of the missing person, going door to door, within the missing person’s neighborhood or by mass mail.
Frequently Asked Questions (FAQ's) on Cold Case Investigations
What is a cold case investigation for a missing person?
A cold case investigation involves the re-examination of an unsolved missing person case where all original investigative leads have been exhausted.
When is a missing person case typically classified as a cold case in California?
A missing person case is typically classified as “cold” after a period of inactivity ranging from one to three years.
What does it mean when a case is considered to have exhausted all leads?
A case is considered to have exhausted all leads when every viable tip, witness, or piece of physical evidence known at the time has been fully investigated without locating the missing person.
Are cold cases legally closed in California?
No. Cold cases remain legally open and on the books, even if they are inactive.
Can a cold case be reopened in California?
Yes. A cold case can be reactivated at any time if new information, tips, or forensic breakthroughs become available.
Why do law enforcement agencies prioritize certain cold cases?
Many agencies prioritize cold cases where there are extenuating circumstances or a strong suspicion that the disappearance involved foul play or homicide.
What investigative methods are commonly used in modern cold case investigations?
Modern cold case investigations use advanced DNA testing, forensic genealogy, comprehensive case file reviews, and database integration.
How is advanced DNA testing used in cold case investigations?
Advanced DNA testing methods, such as Short Tandem Repeat (STR) and mitochondrial DNA analysis, are used to test biological evidence that was previously too small or degraded to analyze.
What is forensic genealogy and how is it used?
Forensic genealogy involves comparing DNA from unidentified remains or crime scenes against public genealogical databases to help identify missing persons or potential suspects.
Why are original case files reviewed in cold case investigations?
Specialized investigators review original reports to identify overlooked discrepancies, missed leads, or investigative gaps from the initial inquiry.
What databases are used in California cold case investigations?
Investigators commonly use databases such as the National Missing and Unidentified Persons System (NamUs) and CODIS to cross-reference missing person reports with unidentified human remains across jurisdictions.
What are Cold Case Units?
Cold Case Units are specialized law enforcement teams dedicated exclusively to long-term unresolved cases to ensure they continue to receive investigative attention.
Who typically works in Cold Case Units?
These units are often staffed by experienced detectives and, in some cases, retired officers with extensive investigative backgrounds.
Why do families sometimes hire private investigators for cold cases?
Families may hire private investigators because they can dedicate full-time attention to a single case, unlike law enforcement agencies that must prioritize active emergencies.
Statistics on Missing Adults in California
In the State of California, the Department of Justice is responsible for maintaining statistics on missing adults. In 2024, there were:
- 1,639 Dependent Adults reported missing
37,187 Voluntary Missing Adults who left on their own free will
2,414 who disappeared under Unknown Circumstances.
Below is a graphic of the 2024 Annual Missing Adult Report:
