for their crackdown on illegal immigrants and their controversial sheriff who says he's just doing the job he was elected to. >> we go out with my volunteer posse. i have 3,000 volunteer posse, about 400 carry guns. >> you sound like a cowboy. >> no. yeah, you know, i do act like a cowboy. but instead of going after horse thieves, i go after car thieves. things have changed. >> sheriff joe arpaio joins us. also tonight, that fence along the border, a lot of big promises made over the years. a lot of money spent, $2.5 billion. four years gone by so far. the work is mostly done but the fence isn't and it's probably not what you expect.