Chain of custody is the documented handling history of evidence used to show that the item remained identifiable and untampered with.
Chain of custody is the documented history of how evidence was collected, stored, transferred, and handled so the court can evaluate whether the item remained identifiable and untampered with.
Chain of custody matters because physical evidence is only useful if the court can trust what it is and where it came from. Weak documentation creates room for arguments about substitution, contamination, or mishandling.
The term is especially important in criminal cases, but it also matters in civil and administrative settings whenever real-world objects, samples, or records need to be authenticated.
It appears in criminal trials, forensic reports, police evidence logs, suppression disputes, and trial objections about whether physical evidence should be admitted or given much weight.
Police seize a phone under a search warrant and log each transfer from the evidence room to the forensic lab and back to court. That documentation helps establish the chain of custody.
Chain of custody concerns the handling history of evidence. Direct evidence and circumstantial evidence describe how evidence proves a fact. Chain of custody does not tell you whether the item proves guilt by itself; it helps show the item is the same evidence originally collected.