See #56.
“About a year ago I checked the last seven presidents of the Harvard Law Review against the archived HLR online. NONE of them had published any articles in the HLR, although a couple were credited in footnotes with assistance (as Obama was).”
That covers the last seven years, when the position was no longer based on merit.
Also, I just checked the HLR site and here’s what I found...
http://www.harvardlawreview.org/about.php
The last paragraph states that student’s writing in the Review is unsigned, so from that alone we can’t tell who wrote what. But it is widely accepted that Obama contributed only one article to the Review.
Here’s another article (written by Obama himself in 1990) on the selection process and the controversy even then of the part that affirmative action played in his selection.
http://www.hlrecord.org/2.4475/record-retrospective-obama-on-affirmative-action-1.577511