NYT:
This is a scene from the city’s benign-sounding but often raucous Citizens Air Complaint Program, a public health campaign that invites — and pays — people to report trucks that are parked and idling for more than three minutes, or one minute if outside a school. Those who report collect 25 percent of any fine against a truck by submitting a video just over 3 minutes in length that shows the engine is running and the name of the company on the door.
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Some of those complaints turn menacing when truck drivers react.
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The camera around his neck has no film. The flip phone does not work. They are distractions from what is really going on, which he asked not be explained in detail and thus revealed to the truck drivers — suffice it to say it involves an iPhone that he is not holding in his hands while it records. And lots of pretend calls on the flip phone.