If you're not familiar with Judge Posner, you should be. He's been a judge in the Court of Appeals (a set of courts right below the Supreme Court) since 1981. In addition to being a judge, he is the most cited legal scholar of the 20th century. He's only the only judge on the 7th circuit to reliably send clerks to the Supreme Court (indeed, Lawrence Lessig was one of those clerks). In short, he's an extremely acclaimed and well regarded jurist. And to boot, his opinions are a pleasure to read (http://www.projectposner.org/case/) and sometimes quite biting (http://www.ca7.uscourts.gov/tmp/LZ19Y7FG.pdf).