# Dragnet **Entity class:** Law-enforcement metaphor and strategy **Domain:** Policing / screening / counterterrorism **Maturity:** Developed ## Definition A **dragnet** is a broad collection or screening strategy that brings a large population of people, records, or events into an initial net so a smaller set of matches can be selected for attention. The metaphor comes from fishing and is used both by practitioners describing interception at borders or chokepoints and by critics describing indiscriminate surveillance. In a counterterrorism identity architecture, the net is not one database. An upstream repository such as [[wiki/Terrorist Identities Datamart Environment|TIDE]] supplies identifiers; downstream watchlists and screening systems compare those identifiers against travelers or encounters. Match rules, error correction, minimization, audit, and redress determine whether the architecture acts as targeted screening or uncontrolled bycatch. ## Relationships - **identity backbone:** [[wiki/Terrorist Identities Datamart Environment|TIDE]]. - **operational process:** [[wiki/Screening|Screening]]. - **analytic expansion:** [[wiki/Contact Tracing|Contact Tracing]] and [[wiki/Link Analysis|Link Analysis]]. - **risk:** false positives, bycatch, net-widening, and chilling effects. ## Sources / Provenance - [Michael D. Bayer, *The Blue Planet* (National Defense Intelligence College, 2010)](https://www.govinfo.gov/content/pkg/GOVPUB-D5_200-PURL-gpo6214/pdf/GOVPUB-D5_200-PURL-gpo6214.pdf) - [NCTC — TIDE fact sheet](https://www.dni.gov/files/Tide_Fact_Sheet.pdf)