Dean of the Yale University law school, appointed to be chief legal advisor to the State Department. Others have been willing to discuss concerns about his questionable stance on U.S. sovereignty and U.S. vs. international laws; see this and this.
What no one else is willing to discuss is that Koh either knowingly supports massive illegal activity and corruption, or he's not smart enough to figure out that he supports those things. In July 2007, Koh said the following about the opponents of New Haven's scheme to hand out city ID cards to illegal aliens:
I'm not sure how their life is diminished by people being able to prove they're part of the city.
What Koh can't figure out is that illegal immigration is a symptom of massive government corruption, as politicians turn a blind eye to or otherwise enable illegal activity for personal gain, either financial or electoral. It's also an indication of private corruption, as businesses such as banks attempt to profit from money that was earned illegally. Not to mention illegal immigration's involvement with crimes such as identity theft and so on. Just because an illegal alien is able to get an "Elm City Card" doesn't mean they also don't need other forms of ID, such as a social security number. Whether the number an illegal alien uses is just made up or belongs to a U.S. citizen, they'll still be taking part in illegal activity.
Not only did Koh say the quote above, but he pledged his law school's resources to help defend the city against law suits. He didn't do so reluctantly or only as a legal principle, but because he supports giving ID cards to illegal aliens and, whether he knows it or not, supports massive illegal activity and public and private corruption.
Ask yourself: what sort of law school dean and State Department legal advisor would knowingly support such a sleazy web of illegal activity, or wouldn't be able to figure what they were supporting?
Harold Koh is either too unintelligent or too corrupt to be given such an important position.