A woman who accused Florida football players Antonio Callaway of sexually assaulting her and Treon Harris of attempted sexual assault in December is boycotting a Title IX hearing because the university appointed a Gators football booster to adjudicate the case.

According to a letter obtained by ESPN, the woman's attorney, John Clune of Boulder, Colorado, informed Florida's deputy general counsel that the complainant, her parents and five witnesses will not attend Callaway's student conduct code hearing, which is scheduled for Friday in Gainesville, Florida.

"This has been a difficult decision but as I previously indicated to you, the fact that UF has hired a football booster to adjudicate a sexual assault allegation against one of the team's own football players is a fundamentally skewed process in which [the complainant] refuses to participate," Clune wrote in letter sent Friday morning to UF deputy general counsel Amy Hass.

"To be clear, [the complainant] remains very willing to participate in a fair and unbiased disciplinary process. Mr. Calloway's behavior has had a great impact on her life and continuing as a student at UF is of great importance to her and her future."

In January, Florida suspended Callaway and Harris for violating the school's code of conduct policy. They were barred from campus and took online courses during the suspension. According to sources, the woman reported the incident to Florida's student conduct and conflict resolution office in early December. She didn't report the incident to police.

Gainesville police and University of Florida police previously confirmed to ESPN that they didn't have reports related to the alleged incident.

University of Florida officials appointed attorney Jake Schickel, a booster for both the Gators' football and basketball teams, to a Title IX hearing involving a woman accusing football players Antonio Callaway and Treon Harris of sexual misconduct. Sam Greenwood/Getty Images

The U.S Department of Education allows schools to establish their own structure for adjudicating Title IX complaints within certain guidelines and standards. The agency requires anyone involved in the grievance procedure to have adequate training in handling complaints of sexual harassment and sexual violence -- and to be unbiased. A letter the agency sent to colleges and universities in 2011 states, "a school's investigation and hearing process cannot be equitable unless they are impartial. Therefore, any real or perceived conflicts of interest between the fact-finder or decision-maker and the parties should be disclosed."

Florida officials appointed attorney Jake Schickel to serve as a hearing officer. Schickel, a founding partner of a Jacksonville, Florida, law firm, has a bachelor's degree in political science and law degree from Florida. He is also a past trustee of Florida's Levin College of Law.

A former track and field athlete at Florida, Schickel, 68, is a Scholarship Club donor to Florida Football Boosters, which requires annual contributions of $4,800 to $8,599, according to a 2014-15 Year In Review program published by the UF athletics department. According to the documents, Schickel is also a 3-Point Club donor to Florida basketball, which requires annual contributions of $2,000 to $4,999.

"To be clear, this letter is not intended to cast any aspersions about Mr. Schickel's character or his service to his alma mater," Clune wrote in an Aug. 2 letter to Hass. "However, UF should never have asked him to serve as an objective reviewer and decision-maker on this matter when the claim has been brought against a star member of the very team for which both he and his law partners have provided considerable financial support.

"Quite frankly, short of finding a relative of Mr. Calloway, I'm not sure how UF could have found someone with more conflicts [than] Mr. Schickel."

Janine Sikes, the university's assistant vice president for media relations and public affairs, issued a statement Thursday afternoon saying that Schickel is qualified to preside over the hearing.

"Any hearing officer and all committee members are trained and vetted for their impartiality," Sikes' statement said. "A hearing officer or committee member would not be disqualified or lack objectivity simply because he or she had been a student athlete decades earlier or purchases athletic tickets as more than 90,000 people do each year."

Florida officials, citing confidentiality laws, declined to say whether it routinely hired Schickel to oversee student judicial hearings, and Schickel did not respond to interview requests from ESPN.

"This is beyond unacceptable," Clune told ESPN. "I couldn't be more proud of my client for boycotting this hearing and she'll take her testimony and her witnesses elsewhere. Victims are not required to settle for whatever scraps of fairness are left over in a biased university process. They get a full seat at the table just like the accused, football player or not. If Florida wants to clear their athlete to play, so be it."

Brett Sokolow, executive director of the Association of Title IX Administrators, a nonprofit association for schools, colleges and universities, said if Florida is choosing someone with such deep ties to the athletic department and university, it opens up any potential decision to a complaint to the U.S. Department of Education or a Title IX lawsuit.

"The obligation for a Title IX investigation is for it to be impartial and completed by somebody whose perspective is objective. All of those associations with the university certainly raise the issue of potential bias," he said. "How would the alleged victim feel like she's getting a fair shake?"

"I'm not even sure it's ethical under the state ethics rules for the attorney to take on this engagement, given his donations and other boosting of the athletic program," he added.

He said any such conflicts should have been disclosed to both sides of the Title IX complaint. Clune said the information was not disclosed and that his firm discovered it on its own.

Harris, a junior from Miami, announced last month that he was leaving Florida and transferring to another school. Sources familiar with the case told ESPN that Harris agreed to leave Florida as part of a plea deal related to the Title IX case. He also apologized to the woman, the sources said.

Callaway, a sophomore from Miami, has maintained his innocence and planned to fight the allegations in Friday's student conduct code hearing.

According to his law firm's biography, Schickel previously worked as an assistant state attorney and chief assistant attorney for the Fourth Judicial Circuit in Florida. He is also a fellow of the American Bar Foundation, adjunct professor at the Florida Coastal School of Law and past president and member of the American Board of Trial Advocacy, according to the bio.

In the letter sent Friday, Clune also objected to Florida officials allowing the woman's past sexual history to be included in the hearing materials. "UF had previously assured [the complainant] and her advisor that UF does not tolerate such 'slut-shaming' tactics and that per UF policy, all such information would be excluded from the process and that any material that had previously been submitted by Mr. Calloway would be placed under seal and not given to the hearing officer," Clune wrote.

Amy E. Osteryoung, the attorney for Callaway, said Clune is being "inappropriate" and making "an attempt at intimidation."

"We are not going to besmirch his client in the press," Osteryoung said in a statement. "The totality of the investigation, which is over 1,000 pages, will do that for us."

Clune's letter also said he emailed Hass "suggestions of organizations that can connect you with independent hearing officers that aren't boosters of Mr. Calloway's football team. I have put your office in touch with the Department of Education, Office for Civil Rights, who has expressed their concern about the impartiality of the hearing officer. Nonetheless, these efforts have all fallen on deaf ears and UF seems even more determined to move forward with their selection."

It is not uncommon for universities to appoint independent officers to adjudicate student conduct code hearings. When former Florida State quarterback Jameis Winston was accused of sexually assaulting FSU student Erica Kinsman in December 2012, FSU officials offered Winston and Kinsman the choice of three former Florida Supreme Court justices to hear their case.

Winston and Kinsman were each allowed to reject one of the justices, and they settled on Major Harding, a former state Supreme Court chief justice. Harding received his undergraduate and law degrees from Wake Forest University and a master of laws degree from the University of Virginia.

Clune also represented Kinsman. FSU paid her a $950,000 settlement earlier this year. Her federal civil lawsuit against Winston is set to begin in April in U.S. District Court in Orlando.

Sokolow said all colleges and universities right now are trying to show the public that their Title IX processes are ones of integrity. When situations arise that make it look like a "fix" is involved, he said, "we've failed to uphold a sacred public trust."

As a freshman last season, Callaway was Florida's leading receiver with 35 catches for 678 yards with four touchdowns in 14 games. He also returned two punts for touchdowns. He was suspended from participating in football activities and missed spring practice before returning to campus for classes in June. Callaway practiced with the Gators for the first time this year on Wednesday, but hasn't been fully reinstated to the team, according to Gators coach Jim McElwain.

"To get a guy who took a ton of snaps, anytime you get that kind of experience it obviously helps," McElwain told reporters this week.