Methodology

How this works

This page explains how we decide what goes on the map, what each label means, and where we draw the line between “documented” and “confirmed.”

What the labels mean

Agency record. A location that came directly from a government agency—an inventory, deployment list, map, contract attachment, or similar primary record.

Field confirmed. Someone observed the equipment directly, or we have geotagged field evidence showing it was there on a particular date. That doesn't prove it stayed there or kept operating afterward.

811 installation candidate. A utility-locate record tied to installation work. It tells us work was planned or carried out there; it doesn't prove a camera is installed or active today.

Crowd mapped. A location mapped by OpenStreetMap/DeFlock contributors. These points can be very precise, but they're maintained by the community rather than confirmed by an agency.

Record derived. A location pulled from a released public record that still needs stronger support before we treat it like a primary location.

Other. Useful evidence that doesn't fit one of the stronger categories yet. We keep it visible and label it honestly instead of quietly upgrading or discarding it.

Where each point comes from

We keep track of where each published record came from and, when we can, the exact reference behind it. If an agency gives us a street address and we turn that address into map coordinates, we say so—we don't call those coordinates agency-supplied GPS.

If an official record names a location but we can't place it confidently on the map, it stays unresolved. We'd rather show a gap than make up a coordinate just to make the map look complete.

When records become one site

Several records can describe the same physical installation. The default map tries to group those records when different sources line up closely enough, while keeping every original record underneath. We deliberately err on the side of showing a duplicate rather than merging two real sites into one.

• If two different source types land almost on top of each other—within 3 meters—they may be grouped.
• A Flock 811 record and an OSM/DeFlock point may be grouped when they're within 20 meters.
• A Flock agency record and an OSM/DeFlock point may be grouped when they're within 15 meters.
• A field-confirmed point may be grouped with another source type within 15 meters.
• A manually reviewed point may be grouped with another source type within 10 meters.
• Two points from the same source aren't merged just because they're close together.
• No grouped site is allowed to spread more than 20 meters from one member record to another.

An estimated installation site is not a camera count. One site can contain several devices, and several records can describe the same installation.

Where it is and how sure we are

Where we draw a point and how strong the evidence is are two separate questions. A community-mapped point may give us the best physical coordinates, while an agency record gives us the stronger evidence that the installation exists.

What stays private

The public site only gets the research data needed to understand the map. We don't publish email bodies, private recipient addresses, credentials, OAuth material, portal tokens, internal notes, private database fields, or license-plate histories.

Search and filtering happen in your browser. We don't run our own behavioral analytics on you.

If something's wrong

Sources can be wrong, duplicated, outdated, or later contradicted. If you spot a problem, tell us which location or record is affected, what looks wrong, and—if you have one—the source that supports the correction.

Correction and change-log policy

This is our research rulebook, not a promise that every public source is complete, current, or correct.