CHAPEL HILL, N.C. -- A three-month investigation into academic fraud at the University of North Carolina revealed that not only student-athletes were given added academic benefits within the school's African and Afro-American Studies department.

Rather, students at large benefited from anomalies specific to the department, such as unauthorized grade changes, forged faculty signatures on grade rolls and limited or no class time.

"This was not an athletic scandal," former North Carolina Governor Jim Martin told UNC's board of trustees. "It was an academic scandal, which is worse."

The independent investigation, headed by Martin, shows that irregularities in the African and Afro-American Studies department went back further than an original probe revealed -- to fall 1997.

However, according to the report presented to the board Thursday, no academic misconduct or other anomalies were found outside the AFAM department.

Athletic director Bubba Cunningham said the report was forwarded to the NCAA on Thursday morning and he hopes the findings will help his department and school move forward.

"I feel like it's now complete," Cunningham said. "This report has been very thorough, an exhaustive study. From that standpoint, we've been looking for closure, and I hope this gives us the closure we've been looking for."

Martin and consulting firm Baker Tilly compiled almost two decades' worth of enrollment data, looking at more than 172,000 course sections involving almost 120,000 undergraduates and almost 13,000 instructors. They also interviewed dozens of staff, students and officials, and concluded that no faculty member in AFAM was involved unethically in the scandal other than former chairman Julius Nyang'oro and former administrator Deborah Crowder.

According to the report, the review found 216 classes with proven or potential problems, including 454 unauthorized grade changes.

But the report also stated that the percentage of unauthorized grade changes for student-athletes was consistent with student-athlete enrollment in those courses.

"The athletic department, coaches and players did not create this," Martin told the board of trustees. "It was not in their jurisdiction, it was the academic side."

There is evidence that employees of the student-athlete support program were aware that certain courses within AFAM were so-called "Term Paper Courses" that were being taught as independent studies, according to the report.

"When these concerns were raised, the Faculty Athletic Committee stated that it was incumbent upon each instructor of record to determine how to teach his/her own course and that is was therefore unnecessary for ASPSA (Academic Support Program for Student Athletes) personnel to question the instructional methods used," the report stated.

Martin also told the board he found no evidence that any coaches knew anything about the irregularities.

"I believe personally that the big money from television contracts does distort values of collegiate sports programs; but we found no evidence that it was a factor in these anomalous courses," Martin wrote in the report. "Despite what one might imagine, there is no evidence the Counselors, or the students, or the coaches had anything to do with perpetrating this abuse of the AFRI/AFAM curriculum, or any other."

He also wrote that there were many other ways, within the rules, for athletes and other students to get high grades and boost their GPAs outside of the AFAM department.

In May, UNC publicly announced an internal probe found that 54 classes in the department of African and Afro-American Studies were either "aberrant" or "irregularly" taught from summer 2007 to summer 2011.

UNC said no student received a grade without submitting written work. But more than 50 percent of the students in those suspect classes were athletes. As first reported by The Raleigh News & Observer, one class in summer 2011 had an enrollment of 19 -- 18 football players and one former football player.

In late July, a faculty committee looking into the scandal issued a new report, stating that academic counselors assigned to the athletes may have pushed them into those classes.

In August, a partial transcript of former two-sport star Julius Peppers was uncovered by North Carolina State message board posters on UNC's website. His alleged low grades and class choices raised questions about how far back problems in the AFAM program go.

That put more pressure on school chancellor Holden Thorp and UNC, which requested Martin and consulting firm Baker Tilly to conduct an independent review.

An NCAA spokesperson did not immediately respond Thursday morning to an email seeking comment on the matter.

UNC says it shared the results of its original internal probe with the NCAA before the NCAA sanctioned the football program in March for improper benefits and academic misconduct involving a tutor.

UNC again updated the NCAA enforcement staff on Aug. 23 about the AFAM situation, and the school released a statement a week later that said: "The NCAA staff reaffirmed to university officials that no NCAA rules appeared to have been broken."

Thorp said Thursday that if the NCAA has any further questions, the school will address them. Cunningham did not want to speculate on how the NCAA might respond.

The attorney for former UNC football coach Butch Davis -- who was fired during the summer of 2011 amid the ongoing probe into extra benefits within the football program and academic misconduct -- also responded to the report Thursday, saying it further vindicated his client.

Davis wasn't cited for a violation when the NCAA announced sanctions against the program last March.

"For the past two years, a few loud voices in this community have clamored that Butch Davis has somehow tarnished the reputation of the University of North Carolina," attorney Jon Sasser said in a prepared statement. "The Martin Report has confirmed that the opposite is true. ... Separate investigations by UNC, the NCAA, and Gov. Martin have now unanimously concurred with what those who have worked with Coach Davis already knew: He has always valued education, and he has consistently honored the letter and spirit of the rules."