(CNN) A police report obtained by CNN bolsters evidence that legendary football coach Joe Paterno knew years before Jerry Sandusky's arrest that his longtime assistant might be sexually abusing children.

The one-page Pennsylvania state police report, obtained from a source and described here for the first time, lays out an account from whistleblower Mike McQueary, who reported to Paterno an incident he had just witnessed in a locker room between Sandusky and a young boy. Paterno allegedly told McQueary in 2001 that the claim against Sandusky "was the second complaint of this nature he had received," according to the police report, which was written after Sandusky's arrest 10 years later.

McQueary's claim of abuse and other allegations led to Sandusky's conviction in 2012 for sexually abusing 10 boys over 15 years, including three victims after the 2001 locker room incident. He is serving a sentence of at least 30 years in prison. An appeal is pending

The police report casts fresh doubt on the mountain of denials by Paterno, his family and his loyalists that the coach knew anything of Sandusky's serial molestation before the 2001 incident.

It contradicts the head coach's testimony before a grand jury and his published statement a week before he died in 2012 that he "had 'no inkling' that Sandusky might be a sexual deviant" until he heard the shocking allegation from McQueary. Other documents unveiled since Paterno's death suggest the head coach was told of other similar claims as early as the 1970s.

The police report's absence from the public record -- until now -- also offers a glimpse into the courtroom strategy that led to Sandusky likely spending the rest of his life in prison.

'Second complaint of this nature'

McQueary, a one-time Penn State football assistant who became the star witness in the case against Sandusky, told state police in 2011 that he'd visited Paterno on a Saturday morning 10 years earlier to tell him that the previous evening he had witnessed "an extreme sexual act occurring between Sandusky and a young boy" in a football locker room shower, according to the report by Pennsylvania police.

"Paterno, upon hearing the news, sat back in his chair with a dejected look on his face," the report states, adding that McQueary "said Paterno's eyes appeared to well up with tears."

"Then he made the comment to McQueary this was the second complaint of this nature he had received about Sandusky," the report states, citing McQueary's recollection.

Paterno and McQueary had "no discussion of the previous complaint at that time or any other time," the report states.

The police report also notes, again according to McQueary, that Paterno told the young assistant that his wife, Sue Paterno, once had told the head coach that Sandusky's wife, Dottie Sandusky, "told her Jerry doesn't like girls."

Attorneys for the Paterno family and for Dottie Sandusky did not respond to CNN's requests for comment.

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McQueary never testified publicly about the police report or the new details it reveals. The report was written days after Sandusky's arrest in 2011, soon after the 2001 allegation first came to the attention of police.

McQueary did testify at least twice about Paterno's reaction in 2001 to the allegation involving Sandusky, but the whistleblower never was asked under oath -- nor did he volunteer -- the detail about the "second complaint," records reviewed by CNN show.

Still, prosecutors consider the police report -- part of a much larger state police dossier on the Sandusky case -- a credible version of events, two people close to the case told CNN.

The courtroom strategy

That McQueary's statement to police is only now coming to light is no accident.

McQueary, who is now writing a memoir about the Sandusky drama, always was careful in his testimony not to elaborate unnecessarily or volunteer information he wasn't asked, another source close to the case told CNN. In fact, witnesses typically are advised by defense lawyers, prosecutors and judges to stick to the question at hand.

McQueary also was under intense public pressure from Paterno supporters who long have insisted the head coach knew nothing of Sandusky's crimes before he heard McQueary's claim in 2001. Beyond that, McQueary -- "out of respect" -- did not want to needlessly disparage the deceased Paterno, the third source said.

And that was fine with prosecutors, the initial two sources said. Authorities feared their chances of convincing jurors to convict Sandusky would plummet if the trial became about Paterno, a beloved figure for generations whose legacy was deeply tarnished by Sandusky's crimes and whose knowledge of the former coach's misdeeds remains the subject of emotional debate to this day.

"We structured the whole case around avoiding Penn State," a source close to the prosecution said. "We were terrified (of acquittal)."

Indeed, in his opening remarks to Sandusky's jury, lead prosecutor Joe McGettigan said, "The Pennsylvania State University is not on trial." McGettigan wouldn't comment for this story.

Prosecutors even warned Sandusky's defense attorneys against raising the "Penn State issue" at trial and threatened to pile on older evidence against Sandusky if they did, the two initial sources told CNN.

"They hated the whole Penn State conspiracy thing," the source close to the prosecution said of jurors. "We totally structured the case to avoid Paterno."

Some authorities in the case have said they never found evidence Paterno committed any crime in connection with Sandusky's abuse, though some also have said Paterno could have done more to stop his assistant.

It's something Paterno himself admitted in November 2011.

"I wish I had done more," he said after he was dismissed from Penn State after 46 years as its head football coach.

And it was a point echoed by a judge in June when he sentenced the three ex-Penn State administrators to jail in connection with the case.

Paterno could have called the police in 2001 "without so much as getting his hands dirty," the judge said.

'I did not know of anything'

Speculation has festered since Sandusky's arrest about what Paterno knew of his assistant's crimes and when he learned it.

Fervent supporters have pushed the narrative that Paterno was ignorant of Sandusky's offenses until 2001 -- and have tried to discredit people connected to the case, including victims, who dispute that theory.

The police report's reference to Paterno's mention of a "second complaint," according to McQueary, now raises new questions on that front, including about what Paterno told a Pennsylvania grand jury.

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The head coach was asked under oath in 2011: "Other than the incident that Mike McQueary reported to you, do you know in any way, through rumor, direct knowledge or any other fashion, of any other inappropriate sexual conduct by Jerry Sandusky with young boys?"

Responded Paterno: "I do not know of anything else that Jerry would be involved in of that nature, no. I do not know of it. You did mention -- I think you said something about a rumor. It may have been discussed in my presence, something else about somebody."

Paterno the following year cleared up any inference to rumors. In his interview with The Washington Post's Sally Jenkins , the head coach said he had "no inkling" of allegations against Sandusky before 2001.

Indeed, Paterno said that when McQueary told him at that time about the locker room incident, he didn't quite understand the story because he'd never heard of "rape and a man," The Post reported.

Paterno relayed what McQueary told him to two top Penn State officials, though he waited a day to do so because "I didn't want to interfere with their weekends," he told the grand jury. Paterno told The Post he "waited 'til Sunday because I wanted to make sure I knew what I was doing."

Paterno and McQueary at that point left the issue to higher-ups at Penn State, they've said. Those administrators opted to handle the matter internally by advising Sandusky to get "professional help," according to trial testimony.

Paterno and earlier allegations

Since Paterno's death in 2012 from lung cancer, civil settlements between Penn State and Sandusky's victims have revealed other claims that the head coach knew long before 2001 of allegations related to Sandusky. Two men claim they reported their abuse directly to Paterno in the 1970s.

One man, dubbed John Doe 150, alleged that Paterno dismissed his report of molestation by Sandusky in 1976, saying, "I have a football season to worry about," court documents show. And in the 1980s, assistant coaches reportedly shared their concerns about Sandusky with Penn State officials, the settlements revealed.

"I have touched base with Coach," Ex-Penn State Athletic Director Tim Curley wrote in an email in 1998 regarding the claim against Sandusky.

Curley testified this spring that he had a conversation in 1998 with Paterno about that allegation. Curley, who pleaded guilty to misdemeanor child endangerment related to Sandusky's crimes, testified for the prosecution in the trial of ex-Penn State President Graham Spanier.

to the 1998 case because they were made public after his death. Paterno was never asked about the emails relatedto the 1998 case because they were made public after his death. His family initially slammed Freeh's report as "factually wrong," though this summer they dropped their lawsuit against the NCAA over actions the organization took based on Freeh's findings. The estate asked that the matter be "discontinued with prejudice," meaning it can't be refiled.

"Our goal has always been to uncover and make transparent the full truth," Sue Paterno said in a statement. "We have done all we can in this litigation to achieve that end and the furtherance of it beyond this point will not yield anything new, which is why I have decided to end my litigation with the NCAA."

Freeh's report, which Penn State commissioned for $6.5 million, is no longer available at the university's website, a Penn State spokeswoman confirmed.

Degrees of detail

McQueary's police interview was conducted by a state trooper on November 23, 2011, just two weeks after Sandusky's arrest. It followed up on an earlier interview and focused on McQueary's conversation with Joe Paterno on that Saturday morning in 2001. The trooper could not be reached for comment.

McQueary went on to testify, sometimes behind closed doors, in five criminal cases and at least four civil cases related to the Sandusky scandal, including his own case, which yielded a $12 million judgment against Penn State for defamation.

Each time, McQueary recounted how he had witnessed Sandusky engaging in a sexual act with a prepubescent boy late one night in 2001 in a locker room, where McQueary had gone to retrieve some shoes.

A CNN review of McQueary's public testimony shows he never shared under oath the police report's detail about Paterno's mention of an earlier complaint regarding Sandusky. That squares with sources' explanation of efforts to keep the spotlight off Paterno.

Photos: Paterno as Penn State coach Photos: Paterno as Penn State coach Former Penn State football coach Joe Paterno died in January 2012. He was 85. The legendary coach, seen here in 1988, was fired in November 2011 amid revelations that assistant coach Jerry Sandusky had sexually abused boys on the Penn State campus. Here's a look at Paterno's 46 years at the helm of the Nittany Lions football program. Hide Caption 1 of 12 Photos: Paterno as Penn State coach The statue of Paterno outside Beaver Stadium was among many vestiges of his years as head coach. After his legacy was tarnished it was removed from its pedestal in 2012. Hide Caption 2 of 12 Photos: Paterno as Penn State coach Paterno sprints off the field with his team at halftime in a 1996 game. Hide Caption 3 of 12 Photos: Paterno as Penn State coach Paterno celebrates after winning the Fiesta Bowl against Texas in 1997. Paterno was diagnosed with a treatable form of lung cancer, his son announced in November. Hide Caption 4 of 12 Photos: Paterno as Penn State coach In October 2001, Paterno is honored before a game for having won the most games in Division 1-A. He continued to vie with Florida State's Bobby Bowden for the most all-time major college wins until Bowden retired in 2009. Hide Caption 5 of 12 Photos: Paterno as Penn State coach Paterno and his Nittany Lions look on before facing Iowa at Beaver Stadium in State College, Pennsylvania, in October 2004. Hide Caption 6 of 12 Photos: Paterno as Penn State coach Paterno shakes hands with Lloyd Carr of Michigan before their game in 2005 in Ann Arbor, Michigan. Hide Caption 7 of 12 Photos: Paterno as Penn State coach Paterno celebrates a triple-overtime Orange Bowl win over Florida State in Miami on January 3, 2006. Paterno has guided his teams to more bowl victories than any other college coach. Hide Caption 8 of 12 Photos: Paterno as Penn State coach Paterno speaks at a post-game press conference after winning the Outback Bowl on January 1, 2007, in Tampa, Florida. Hide Caption 9 of 12 Photos: Paterno as Penn State coach Paterno walks the field as his players warm up before their game against the Syracuse Orangemen at Beaver Stadium in September 2009 in Pennsylvania. The coach was fired in November amid the outcry over the handling of accusations against former defensive coordinator Jerry Sandusky. Hide Caption 10 of 12 Photos: Paterno as Penn State coach Paterno gives direction to his players before playing the Crimson Tide in Alabama in 2010. Hide Caption 11 of 12 Photos: Paterno as Penn State coach Paterno walks the sidelines in October 2009 in Evanston, Illinois. In December 2011, he was admitted to a hospital after fracturing his pelvis when he slipped and fell at his home in State College. Hide Caption 12 of 12

McQueary's testimony at various proceedings was brief as it related to Paterno and mostly focused on other defendants in the case, including Sandusky, Spanier, Curley and ex-Penn State Vice President Gary Schultz. The latter three were convicted on misdemeanor child endangerment charges.

McQueary testified in March that Paterno, upon hearing the graduate assistant's allegation in 2001, "slumped back in his chair and put his hand up on his face, and his eyes just kind of went sad." In July 2013, McQueary testified about that same moment, saying Paterno "slumped back in his chair," was "significantly saddened," and even "dropped his eyes a little bit."

Also in his 2013 testimony, McQueary said Paterno in the years after 2001 made passing remarks about how Sandusky "was a sick guy" and said the university "screwed up" in its handling of the 2001 allegation.

Paterno's family has accused McQueary of inconsistency in his retelling of what he saw in the locker room, though prosecutors have praised him for handling several trips to the witness stand matter-of-factly.

Now, five years after McQueary first publicly took the stand, his conversation in 2001 with Paterno is still at the heart of debate over the coach's legacy.