You can give the user the option to self-identify, and then basically ignore it and use an internal index for the actual determination based on their voting pat

You can give the user the option to self-identify, and then basically ignore it and use an internal index for the actual determination based on their voting patterns, etc. I think that's better than punishing people for "being open-minded", i.e., identifying as left-leaning but playing devil's advocate for the right, or finding their political leanings beginning to shift.