You're not going to like this, but this whole thing is an overreaction on your part.
Having spent months at a time touring Mexico in our motorhome, we have learned from our experiences in dealing with Mexican local police. It's part of the culture, and is more prevelant in touristy areas where the tourists are easily intimidated.
Instead of ranting and writing letters, you just need to learn from the experience. Mexico is not United States. learn some of the language, learn some of the culture, and don't be out at 2am in the morning!
Kevin
www.travelwithkevinandruth.com