For your reading pleasure, below is the full report from the SEC's OIG regarding their handling of the various Madoff investigations.  The Executive Summary of the report is also below for those who prefer about 20 pages of reading rather than over 420 pages.

Full report - http://sec.gov/news/studies/2009/oig-509.pdf
Executive Summary - http://www.sec.gov/spotlight/secpostmadoffreforms/oig-509-exec-summary.pdf