He was part of the club, meaning that to outsiders like you and me a "Senior Lecturer" was as good as a Professor. That's the university's line and there is some merit to it.
But inside the club -- among the law faculty -- was Obama's post really as prestigious as, say a full professor with publications to his name? Was his status really as high as that of the school's expert in a whole field of law? Probably not.
No way. He was not "part of the club" as you put it.
Lecturers and adjuncts are not tenure-track, do not have a vote, and are not as good as professors.
He was not even Tenure Track. That meant it was only slightly higher than a TA. Actually, I think it was about three steps above a TA, but not much more.