The Jerry Sandusky Penn State probe, involving years of alleged child abuse by the retired defensive coordinator, keeps getting dirtier, casting a long shadow over the grimy world of college football scandals and forever putting a blot on Penn State football and charity The Second Mile. Sandusky, once considered a likely replacement for football coach Joe Paterno, has been charged with sexually assaulting at least eight young boys over the course of fifteen years, but reports indicate the abuse may have involved more youths, gone on longer, and may have been covered up by high-ranking members of Penn State football and general faculty.

Investigation into ongoing child sex abuse at Sandusky charity foundation The Second Mile began in 2009, when a first official report was filed, and it seemed as though the charges caught the athletic and scholarly community completely by surprise.

Now however, two Penn State officials, Athletic Director Tim Curley and Senior Vice President for Finance and Business Gary Schultz, have been charged with failing to report suspected child abuse. Notes from the grand jury report, the Pennsylvania attorney general's office, and reporting by news outlets like CNN and USA Today show that allegations of abuse, and eyewitness accounts, date back as far as 1994 at least.

Here, a timeline of the course of the explosive sex scandal and its apparent cover-up by members of the Penn State faculty.

1977 -- Jerry Sandusky founds The Second Mile, a state-wide non-profit foundation established to help at-risk youth. The organization's web site describes it as a place to promote self-confidence as well as physical, academic, and personal success.

1994-1997 -- Sandusky allegedly uses The Second Mile grounds to engage in inappropriate conduct with three different boys he met separately through the program. One boy was 7 or 8, the second was 10, and the third was between 12 and 13. According to the grand jury report, the three boys, now grown, say Sandusky's behavior ranged from touching to overt sexual come-ons and sexual assault. Several incidents reportedly took place during home games for Penn State football, when the team, staff and the boys were all staying at a nearby hotel.

1998 -- First police involvement. Penn State police and the Penn. Department of Public Warfare are contacted by the mother of an 11-year-old boy, who says Sandusky showered with her son and may have had inappropriate contact with him.

June 1, 1998 -- In an interview with investigators, Sandusky admits showering naked with the pre-teen. He admits that it was wrong, and promises not to do it again. No charges are filed, and the university police chief instructs that the case be closed.

1999 -- Sandusky retires from Penn State after coaching for 32 years. he remains a volunteer, and retains full access to the campus, football facilities, and The Second Mile camp grounds.

2000 -- Sandusky showers with a young boy and tries to touch his genitals during overnight stays at the coach's house, according to the now 24-year-old man's testimony to the grand jury.

2000 -- First eyewitness report. Tim Calhoun, a janitor at the Lasch Football Building on Penn State's campus, tells another janitor and his supervisor that he saw Sandusky performing oral sex on a young boy. The incident goes unreported.

2000 -- Second eyewitness report. Another janitor sees Sandusky and a boy leave the shower room together and walk out of the building hand in hand, according to the grand jury report. No one reports the incident to university officials or law enforcement.

March 2, 2002 -- A graduate assistant allegedly tells Coach Joe Paterno that he saw Sandusky in the locker room shower on Mar. 1 with a young boy. The retired defense coordinator was engaging in anal sex with the boy, believed to be no more than 10 years old.

March 3, 2002 -- Paterno reports the incident to Athletic Director Tim Curley. Paterno tells Curley the grad student had seen Sandusky fondling or doing something of a sexual nature to a young boy. The graduate assistant is called to a meeting with Curley and Schultz.

March 3, 2002 -- The assistant, according to the grand jury report, sticks by his story, saying he saw Sandusky having anal sex with the young boy. Schultz, 62, and Curley, 57, told the grand jury they could not remember the details of the meeting. Schultz said Sandusky might have inappropriately grabbed the young boy's genitals during wrestling, and Curley said he was under the impression, like Schultz, that the affair involved little more than horsing around.

March, 2002 -- Sandusky's locker room keys are confiscated, and he is told not to bring his Second Mile participants to campus. The incident is not reported to police, and no official investigation is launched.

March, 2002 -- The Second Mile learns of the shower incident through Penn State. Curley tells them that the information had been internally reviewed, and that there was no finding of wrongdoing.

2005 or 2006 -- Sandusky allegedly befriends and molests another Second-Mile participant. These allegation will form the foundation of the multi-year grand jury investigation about to launch.

2006 or 2007 --Fourth known eyewitness report. A wrestling coach at a high school where Sandusky volunteers surprises the former coach and a young boy. The two are allegedly lying on their sides, in physical contact, face to face on a mat. Sandusky jumps to feet, telling the coach the two were practicing wrestling moves, which seemed believable. Later, according to the wrestling coach's testimony, Sandusky begins to spend more time with the boy, taking him to sporting events and giving him gifts like a computer, golf clubs, clothing and cash. Sandusky allegedly performs oral sex on the boy over 20 times, and boy performs oral sex on Sandusky at least once, according to grand jury reports.

2008 -- The boy breaks off contact with Sandusky, and his mother calls the high school to report her son has been sexually assaulted. The principal, Steven Turchetta, bars Sandusky from campus and reports the incident to police, calling Sandusky clingy and needy around the boy. The resulting investigation into the sex abuse claims reveals 118 calls from Sandusky's home phone and cell phone to the boy's home number.

November 2008 -- Sandusky informs The Second Mile that he is under investigation. He is removed from all program activities involving children.

September 2010 -- Sandusky retires from The Second Mile.

Nov. 4, 2011 -- The grand jury report is released.

Nov. 5, 2011 -- Authorities arrest Sandusky. He is charged with seven counts of involuntary deviate sexual intercourse and numerous other charges, including aggravated indecent assault, corruption of minors and endangering the welfare of a child. He is charged with 40 counts in all, 21 of them felonies. Punishment for each of the felonies ranges from seven to 20 years in prison and $15,000-$25,000 in fines. For the 19 misdemeanors, convictions earn two to five years' imprisonment and $5,000-$10,000 in fines.

Nov. 5, 2011 -- Sandusky is freed on $100,000 unsecured bail. Curley and Schultz are each charged with one count of felony perjury for lying to grand jury investigators, and one count of failure to report abuse allegations. They plead not guilty.

Nov. 6, 2011 -- Curley is granted administrative leave to deal with the charges, while Schultz retires.

Nov. 6, 2011 -- Paterno releases a statement calling the charges shocking. If this is true, we were all fooled, along with scores of professionals trained in such things, and we grieve for the victims and their families. Paterno is questioned about the allegations, since 20 of the charges agaisnt Sandusky to date occured while he was Paterno's defense coordinator at Penn State.

Nov. 7, 2011 -- More begin to step forward. There were whispers about it, Alex Ricker, a former Penn State student who has worked several Second Mile camps, told USA Today. But when it came out, I don't think anybody expected that big of a hit or that serious of an indictment, as well as that many charges.

Nov. 7, 2011 -- Pennsylvania attorney general Linda Kelly says Paterno is not a target of the sexual abuse investigation involving his former assistant coach, despite noting his responsibility to report the incidents to law enforcement.

Nov. 7, 2011 -- I understand that people are upset and angry, but let's be fair and let the legal process unfold, Paterno says in a statement. In the meantime, I would ask all Penn Staters to continue to trust in what that name represents, continue to pursue their lives every day with high ideals and not let these events shake their beliefs nor who they are.

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