Kane commissioned the report in January 2013 amid allegations that Corbett, who was the state's attorney general when Sandusky's crimes came to light, sat on the truth to improve his changes at a gubernatorial run.
Corbett's office received the case in 2009. Sandusky wasn't arrested until November 2011.
Corbett ran for governor in 2010. There had been speculation that Corbett timed the investigation so that the case wouldn't break before his gubernatorial run.
The report, which still must be approved for release by a grand jury judge, found that Corbett did not tank the investigation for political reasons, The Inquirer said.
Sandusky, a former assistant coach at Penn State, was convicted in June 2012 of 45 out of 48 counts of child sexual abuse, and is serving 30 to 60 years in state prison.