http://usnews.msnbc.msn.com/_news/2012/07/12/12703724-freeh-timeline-illustrates-penn-states-actions-in-sandusky-case?lite
This timeline makes it pretty clear that Sandusky decided to retire after the investigation.
May-August 1999:
Sandusky writes a letter to Curley saying, because he will not be next head football coach, he is considering retirement. Sandusky also seeks “to maintain a long‐term relationship with the University.”
You'll note this comes after:
May 4-30, 1998:
Victim 6’s mother reports to the University Police Department that Sandusky showered with her 11‐year-old son in the Lasch Building on the Penn State campus. The police promptly begin an investigation.
Schultz is immediately informed of the investigation and notifies Spanier and Curley. Schultz’s confidential May 4, 1998 notes about Sandusky state: “Behavior – at best inappropriate @ worst sexual improprieties” and “At min – Poor Judgment.” Schultz also notes: “Is this opening of pandora’s box?” and “Other children?”
In August 1999, Sandusky is granted “emeritus” rank, which carries several privileges, including access to University recreational facilities.
Documents show the unusual request for emeritus rank originated from Schultz, was approved by Spanier, and granted by the Provost, who expressed some uneasiness about the decision given Sandusky’s low academic rank and the precedent that would be set.
So Vice President Shultz, who in the timeline- "Schultz’s confidential May 4, 1998 notes about Sandusky state: “Behavior – at best inappropriate @ worst sexual improprieties” and “At min – Poor Judgment.” Schultz also notes: “Is this opening of pandora’s box?” and “Other children?” , is now comfortable recommending this emeritus rank? And Paterno knows nothing about all of this?
Come on.