How Long Do Cold Cases Take to Solve?

The two kinds of resolved case

Of the 319 cases, 184 (58%) were broken within a year of the crime or disappearance: an arrest, charge or identification followed the initial investigation. The other 135 went cold first. Among those, the median wait between the crime and the break was 11 years; 71 waited ten years or more and 50 waited twenty years or more. The longest wait in the index is Somerton Man, broken 74 years after the event, in 2022.

For the 268 cases that ended in a conviction, the median gap between the break and the conviction was 1 year; 65 took three years or more from arrest to verdict.

Method and caveats

• Which cases. Every case whose status is Conviction, Solved or Identified: 343 cases. 24 of them have no dated event in their timeline that matches the break rules (for example the suspect died before any arrest, or the victim was found alive) and are left out. Cases with the status Partially Solved, Arrest Made, Pending Trial, Wanted, No Conviction or Ruled Suicide are not counted as resolved.
• The break. The first timeline event, dated in or after the year of the crime, whose text records an arrest, charge, indictment, identification, DNA or fingerprint match, confession or guilty plea. Years are counted as whole calendar years between the year of the crime and the year of that event, so a case broken the next January counts as one year.
• Selection. ColdCaseIndex is a curated index of notable cases, not a random sample of all homicides and disappearances. Famous cases that were solved quickly and famous cases that took decades are both over-represented compared with routine investigations. The figures describe the index, and should be cited that way.
• Dates. Timeline dates are taken from the sources listed on each case page. Where a source gives only a year, that year is used.

The figures are recomputed from the published dataset on every build, so they change as cases are added or their status changes. The rules live in scripts/analysis.py in the site's source. To report an error, email info@coldcaseindex.com.