There was a case recently in America where a grandfather was jailed for a significant part of a year based on a shotspotter localization and no other physical evidence such as gunshot residue.
If citizens in such areas run their own systems they would have a means to provide counter evidence to that provided by shotspotter. Currently they have no means to do that. Even the times of the shots they have to take shot spotters word for it.
Recordings by citizens themselves is an inherently safer approach because their sphere of influence is considerably smaller. Recordings are written to a separate partition on an SD card, it’s pretty simple to encrypt this partition as well if you like, I’ve done that.
For those who are interested each node can be made very cheaply. It will run on a Raspberry Pi zero with a 7 euro GPS. It can also run portably on batteries.
Here are relevant links:
https://github.com/hcfman/sbts-aru
https://hackaday.com/2023/12/30/localizing-fireworks-launche...
https://medium.com/@kim_94237/tdoa-sound-localization-with-t...