No microphone you have to defend.

1. The site enrolled with your station. Done by the site’s manager, revocable at any time, and with an expiry that has to be renewed rather than lapsing into permanence. Enrolling with one station does not enrol with a region or with a national command.
2. Devices agreed with each other. Two or more distinct devices heard it; they stood far enough apart once each one’s own position accuracy was subtracted from the distance between them; the timings were consistent with one sound; and the pattern was plausible for how many devices are actually there.
3. People who were standing there confirmed it. A classifier alone never reaches you. This is the condition that makes a feed defensible while the false-alarm figure stands where it does — and it is the condition that does not exist yet. The step where handsets ask the people holding them whether that was gunfire is being built, and the claim that human answers multiply is a hypothesis until somebody measures it. Until then nothing is eligible to reach an agency at all, by any path. The feed cannot open early by accident.
4. A person released it. Either the site’s manager released it, or the site pre-authorised release and no manager acknowledged in time. Pre-authorisation is off by default and is its own separately-worded setting rather than a line inside a longer consent. An unconfirmed event is unreachable from an agency by any path — including a manager’s manual action. No button bridges that.
5. It is not a drill. Drills are labelled DRILL end to end — on every surface, in the record, and in the payload. One can be sent to you deliberately, as part of an exercise. None can be sent to you accidentally.

Every refusal names which of the five failed, and the site’s manager can see it. A manager asking why the police did not get something gets an answer rather than a shrug, and a silent refusal is indistinguishable from a delivery.

• The floor and the zone where the site has them — “3F East, near the north stairwell” rather than a coordinate. A tie between floors is shown as a tie, and a floor is voted from the devices that heard it rather than solved.
• How many devices contributed, and how many people confirmed.
• The site manager’s number, one tap.
• Acknowledge, en route, on scene, close — each transition timestamped into the record, and the close step is the one section 5 is about.

• Confirmed gunfire
• Fireworks
• Vehicle or machinery
• Other impulsive noise
• Nothing found
• Unable to determine

The reason is specific rather than flattering. The one thing holding this programme’s false-alarm figure where it is, is a library of real negative sounds that cannot resolve finely enough — and no amount of arithmetic fixes that. A disposition is a label on a real event, recorded through the hardware the product actually runs on, in the environment it actually runs in. A few hundred of them are worth more here than another synthetic dataset. That is the whole trade.

Two protections on it, both structural rather than promised. A disposition is never attributed to a named officer in anything this programme keeps — the agency and the instant are enough. And dispositions are held apart from this programme’s own training splits, so a label can never leak into a model’s own test set through a shared recording chain and flatter it.

• A webhook per agency, retried, carrying the incident id, the instant, a point, the geometry type and its parameters, the floor and zone, the tier words, the device count, the confirmation count, the site id and a signature.
• A pull endpoint with a GeoJSON export, because a crime map wants a feature collection rather than a stream.
• A published, versioned schema with a worked example, maintained as a contract rather than as documentation.

None of the above is an argument that a system like this is a good idea for a city. It is the set of answers to the questions that ended the last one.

• A written scope agreed in advance: one station, one enrolled site, a disposition target, and what each side does.
• A published write-up at the end, whichever way it goes — including the case where your own dispositions show a false-report rate you call unacceptable. Then the feed closes and that result is published too. Negative results are recorded here, not discarded.
• No exclusivity, and no condition on any site’s purchase. A site never has to be enrolled with an agency to buy anything, and no sale is contingent on a station saying yes.

One property worth knowing before any of this: the site-manager side already works with zero agencies enrolled. A manager holding an incident sees a short spoken brief and a ladder of local, regional and national numbers, each with the date it was last checked by a person, and dials from their own handset. The software never calls an emergency line itself. So nothing about your station’s workload changes unless you choose to enrol.