Since I know so much about Witchfinder GPS, I'm volunteering with the Witches' Mutual Aid Society on campus, helping improve the jamming perimeter around the school. The current one is pretty outdated, so I designed some amplifiers for the sigils, and introducing spoofing into the mix.
The thing with spoofing Witchfinder is you don't want to inadvertently spoof to a location where there really are witches (which are more common than you think). So we're having some fun picking locations. Mostly known headquarters for hate groups, but also toxic waste sites.
Even though owning Witchfinder GPS is more regulated than it used to be, the worst of the worst can still get their hands of them. And you can't really stop "science." People can just use 3d printers now to make them. So knowing how they work and "out sciencing" them is really the only defense.