SCREENING GLOSSARY · GUIDEUPDATED 2026-09-04
Screening Glossary
Interpol notice vs diffusion: what is the difference?
Diffusions are the part of INTERPOL you cannot see. A diffusion is a request or alert sent by a National Central Bureau directly to chosen countries and recorded at the same time in an INTERPOL police database, without publication to all member countries.
Diffusions exist because a country often needs to alert a few specific neighbours quickly rather than the entire membership. They follow the same colour-coded scheme as notices, red, yellow, blue, green, black, orange and purple, and they must comply with INTERPOL's Constitution and its Rules on the Processing of Data. For a compliance team the significant point is invisibility: a diffusion never reaches the public notice extract, so a public search will not reveal one.
What this workflow covers
SCOPE- Screen the published notice extract, and state that limit explicitly in the evidence file.
- One country can circulate a red diffusion to three neighbouring states to locate a suspect crossing a land border and never ask for a notice.
- The same subject can be the object of a diffusion, then a notice, then neither after a compliance review, so date and scope any statement about INTERPOL status.
- A vendor claiming full Interpol database coverage is describing data that is not publicly available.
Compliance glossary
TERMS- National Central Bureau
- The designated national police unit that connects a member country to INTERPOL and issues its notices requests and diffusions.
- Rules on the Processing of Data
- INTERPOL's internal framework governing what data may be recorded and circulated through its channels, and on what conditions.
Authoritative references
SOURCES- 01About Notices
INTERPOL
- 02Notices — Compliance and review
INTERPOL
Frequently asked questions
Q&A- What is the difference between a notice and a diffusion?
- A notice is published by INTERPOL and sent to all member countries. A diffusion is sent by one National Central Bureau directly to selected countries and recorded in an INTERPOL database at the same time. Both have to comply with INTERPOL's rules.
- Can we search diffusions at all?
- No. INTERPOL publishes extracts of certain notices where the requesting country agrees, and diffusions are not published. Any screening statement touching diffusions should say that the data is not publicly available.
- Can a diffusion be reviewed or cancelled?
- Yes. Diffusions carry the same compliance requirements as notices and are cancelled where they are found not to conform to INTERPOL's Constitution and Rules on the Processing of Data.
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