I don’t doubt your story at all. I have had a few dubious stops over the years. Locals know where the traps are and who is filling a quota, so I rarely get stopped close to home or work, but roads trips are dangerous. I even got stopped by a city cop who said a highway patrol radioed him to stop me for speeding. He admitted I wasn’t speeding when he saw me and then asked me where I lived and could he call me. I was seriously freaked out about cops for a while after that.
One I had was on an Indian reservation, by the "Iroquois Nation Police" or some bogus bunch like that; the highway passed through it for a mile or so. I would have been treated better in Tijuana.