Baylor University did not investigate a sexual assault report made against two football players for more than two years, despite the school's obligation under federal law to immediately address allegations of sexual violence involving students, Outside the Lines has learned.

In 2013, the Waco Police Department wrote in a police report that it had informed Baylor officials about an off-campus incident involving former All-Big 12 tight end Tre'Von Armstead and former practice squad player Myke Chatman. Waco police also told the alleged victim they had contacted Baylor, but according to documents and interviews conducted by Outside the Lines, Baylor didn't begin looking into the allegations until Sept. 11, 2015.

Baylor kicked Armstead off its football team last fall and expelled him from school in February over the allegations, documents obtained by Outside the Lines show. When Baylor coaches announced his suspension from the team, they said it came as a result of a "team rules violation." Chatman was enrolled at Baylor at the time of the incident but left after that semester.

The sexual assault allegation stems from an off-campus incident in 2013. The details and allegations are complicated and, at times, contradictory. Neither Armstead nor Chatman was charged with a crime, in large part because the alleged victim told Waco police she was too drunk to remember exactly what occurred that night and that she didn't wish to pursue charges against the players, given her state of mind.

Armstead, who through his mother and attorney declined to be interviewed by Outside the Lines, has maintained he never had sex with the woman, a fellow student; an appeal of his expulsion from school was denied last week. According to documents obtained by Outside the Lines, Chatman, who did not respond to requests to comment, told Baylor officials in 2015 that the men had sex with the woman.

Police came to the woman's house the night of the alleged assault after her friends called 911 believing that she'd been attacked. Observations by officers at the scene and a rape exam at a hospital revealed bruises, a bite mark and scratches, and witnesses told police they believed they had heard, from downstairs, noises indicative of an assault. But the woman declined to press charges, and Waco police effectively ended the investigation.

Baylor has been under scrutiny for months about how it has handled sexual assaults involving student athletes. In the fall of 2015, Baylor hired Philadelphia law firm Pepper Hamilton to review its past treatment of sexual assault claims. The review has not yet been completed.

In January, Outside the Lines reported several examples in which school officials either failed to investigate, or adequately investigate, allegations of sexual violence. In many of those cases, officials did not provide support to those who reported assaults, in apparent violation of Title IX federal law. Moreover, it took Baylor more than three years to comply with a federal directive to hire a full-time Title IX coordinator, which it did in fall 2014. Last month, one woman, whose story was detailed in the Outside the Lines reports, filed a federal Title IX lawsuit against Baylor. Last week, police began investigating former Baylor player Shawn Oakman for a sexual assault that allegedly occurred on April 3. According to police, Oakman told them he had consensual sex with a woman; the woman accused him of rape.

Oakman was arrested Wednesday, though Waco police haven't formally announced the charges.

Baylor's investigation of the allegations against Armstead and Chatman didn't begin until the alleged victim, encouraged by a friend who had attended a recent sexual assault prevention training program at the school, asked Baylor officials about her case this past September. The school's Title IX report, issued in February and obtained by Outside the Lines, states that the university had been unaware of the allegations until the woman came forward. But Waco police had written in a police report that on April 18, 2013, "Baylor University was contacted." And the woman, who spoke to Outside the Lines on the condition of anonymity, said that police had told her then that they had contacted Baylor and that someone from the university would follow up.

Waco police spokesman Sgt. Patrick Swanton told Outside the Lines on Tuesday evening he did not know whom his department had contacted at Baylor.

Baylor officials declined to answer questions from Outside the Lines. A spokeswoman wrote in an email that "due to the deeply personal and sensitive nature of individual cases and federal law, we do not publicly address specific cases, even when a student shares publicly details or reports of his or her own experience. ... Once a complaint is filed, the Title IX process conducts a prompt and equitable investigation and resolves the complaint fairly." An accompanying statement from university president Ken Starr said in part that Baylor is awaiting Pepper Hamilton's review that will "help us to identify opportunities for action and improvement."

Waco police have never interviewed Armstead or Chatman, according to records and multiple interviews. Waco police's Swanton told Outside the Lines he did not know why neither had been interviewed by police but noted that the woman was "adamant that nothing had happened" during her conversations with police.

As part of its Title IX investigation, Baylor officials questioned Armstead and Chatman in the fall of 2015. Armstead was kicked out of school after an adjudicator determined that he had sex with the woman when she had been too drunk to consent.

Armstead has vehemently denied the accusations and says he never had sexual contact with the woman. He is considering a lawsuit against Baylor, in part, his representatives say, because the school's lack of a timely investigation has made its findings against him unreliable.

"I do not understand that a university with the reputation for Christian values can expel me and find me responsible for an act that has the potential to absolutely ruin my reputation and my future," he wrote in his expulsion appeal. "To do so in a manner that demeans and destroys my personhood relying almost solely on college kids who were almost certainly drinking on a night from two and a half years ago is wrong."

One of the alleged victim's friends lamented the delay in the investigation, too, telling Outside the Lines: "I just wish this [investigation] would have happened right after the incident instead of so long after. Thinking back now, I can just give general details."

McLane Stadium, home to the Baylor football team. ESPN

The night of April 18, 2013, unfolded after a day of campus celebration. Baylor students had been out of classes that Thursday for Diadeloso, an annual school break each spring that has occurred since 1932. Parties abounded on and off campus.

According to Baylor investigatory documents, a police report, and multiple interviews conducted by Outside the Lines, several students gathered at Baylor player Oakman's apartment and began drinking vodka. Some smoked marijuana.

The alleged victim said the last thing she remembers is hanging out in a bedroom with a few other people at Oakman's apartment. The woman, who was 21 at the time, said she knew several of the players through her work volunteering with the athletic department to welcome possible recruits.

Friends at the party disagree about exactly how she was acting, but, at the very least, they say she flirted with Armstead, who was 18 at the time, and Chatman, who was 19. She and the players left the party. Oakman, who has declared for the NFL draft and whose agent declined to comment, told school officials that he cautioned Chatman and Armstead, saying: "Don't go. I wouldn't go."

Witnesses disagree about whether the woman invited them to her house or if they followed her when a friend took her home. They also disagree about whether she, Armstead and Chatman rode to her house in the same car.

A roommate who was home remembered Armstead and the woman going up to the woman's bedroom, while Chatman remained downstairs. She and others noted that Armstead seemed intoxicated but that Chatman did not. The witnesses agree that the woman was intoxicated but did not appear to be so under the influence that she was, as she stated in the police report, blacked out.

Chatman followed the roommate when she went up to check on the woman, and the roommate saw the woman and Armstead in the room, fully clothed and sitting on the bed. Thinking the woman and the two football players were getting ready to leave, the roommate and her friends left the house.

Chatman would later tell Baylor officials that the woman performed oral sex on him while Armstead had sex with her from behind. In the Title IX report, Armstead states he was, "never intoxicated, never touched [the woman] and alleged he was fully aware ... and in his right mind, the entire night."

A different roommate and her boyfriend arrived at the house while the three were in the bedroom. They told police and Baylor officials that they called 911 after hearing "a large bang and 'fists hitting noises' and [the woman] saying, 'No, no, please stop.'" They also said they heard her say, "'No, I don't want it,' at some point in the encounter."

Baylor has been under scrutiny about how it has handled sexual assaults involving student athletes for months. ESPN

The roommate's boyfriend told Chatman and Armstead to leave, and they did. The two witnesses described the woman as incoherent and "almost hyperventilating," with her room in total disarray with curtains pulled down and clothes and blankets strewn on the floor.

When police arrived, they noted the woman was "very intoxicated" and that she had "a bruise on her left cheek and a bite mark on her neck." The officer wrote that the woman "was very adamant that nothing had happened, and that she had not been sexually assaulted," so the officer documented the incident and contacted Baylor officials with details, but did not make an official sexual assault report.

When she woke up the next morning, the woman noticed bruises and pain in her vaginal area. She also heard accounts of the previous night from her friends and Chatman. The next day, she went to the police department to report the incident. "She remembered having a moment of pain in her stomach as if something was too deep inside of her," the report states.

The woman went to the hospital for a sexual assault exam, but when police asked her to sign a form indicating she wanted to prosecute, she declined and said she did not want to press charges.

During a follow-up interview several days later, according to the police report, the woman said "she knows it looks bad because she was drinking and can't remember. She said she ended up making the report because of how her friends said she was acting, and she was bruised. At a minimum, she wants a report made in case they do this to someone else."

The woman told Outside the Lines that she was confident that she had been assaulted: "I would never willingly engage in sex with someone like that, especially with two men at the same time." But she said officers told her that she didn't have a very strong case.

She had told police that Chatman had texted her the day after the incident about what happened, but she had accidentally deleted the texts. Waco police were unable to recover the texts, and the woman responded that "she did not wish to pursue the case since nothing was located on her phone to help."

However, during Baylor's investigation last fall, the university hired a third-party firm to examine the woman's phone. Several text messages from the next two days between the woman and Armstead and Chatman included some messages alluding to sex. And those texts were included with the Title IX adjudicator's report, along with phone records provided by Armstead that also show messages were exchanged, but at different times.

The woman said Chatman also came to her house the next day and talked to her about what happened. Chatman told her that while they were in her room that night, she kept insinuating he and Armstead were in high school, even though they told her they were football players at Baylor. She said Chatman then said, "That's when I realized how drunk you were. That's when I realized this was not a good idea." Chatman initially told Baylor investigators that nothing happened that night, but when confronted with the text messages, he conceded that the three had sex.

By May 23, 2013, Waco police had suspended the investigation without interviewing Armstead or Chatman or requesting their phone records. Police told the woman that Baylor officials had been contacted and to wait for them to contact her, but she never received a call or email from anyone at Baylor, and Armstead didn't either, according to interviews Outside the Lines conducted with several people involved in the reports. Armstead played every game the next season and was the starting tight end in 2014, after which he earned All-Big 12 honors.

Chatman, who left Baylor after the 2012 season, played the past two seasons at Sam Houston State University.

The woman also told "Outside the Lines" that she told some of her professors what happened. The alleged assault happened days before final exams, and the woman said her grades turned out so poorly that she needed to repeat a semester. When her grades dropped to the point where she lost her academic scholarship, she said she petitioned the financial aid office each following semester for the scholarship to be reinstated. She wrote on the petition form "I was sexually assaulted by 2 Baylor football players during the Spring 2013 semester. As a result, I did not perform well in the classes I was taking at that time." Her scholarship was reinstated, she said, but no one contacted her about the assault during her time as a student at Baylor.

The woman also stopped volunteering for the athletic department. She was a work-study employee at Baylor as well and said she attended a sexual harassment speech for employees while still at the school.

"I ran out about 20 minutes into it, and had one of the biggest anxiety and panic attacks. I almost passed out," she said. "That's basically what the rest of my life at Baylor looked like." She graduated in December 2014.

Former Baylor tight end Tre'Von Armstead celebrates after a game in November 2014. Brett Deering/Getty Images

Despite being a private school, Baylor is required by federal law -- Title IX -- to thoroughly investigate allegations of sexual violence, and provide security, counseling services and academic help to those who report assaults. Part of the law's goal is to help keep victims in school.

Baylor's Title IX investigation into Armstead began in mid-September last year, just weeks after a Waco jury had convicted former Baylor defensive end Sam Ukwuachu of sexual assault.

The school made its determination to expel Armstead on Feb. 3, 2016, days after an Outside the Lines investigation into the sexual assault cases of Ukwuachu and former Baylor player Tevin Elliott landed. The stories prompted a campus and community outcry and a candlelight vigil at university president Ken Starr's residence.

Baylor's report noted that the woman was too drunk to consent to sex and that Armstead should have known that. It also stated Armstead's credibility was damaged after witness testimony and text messages showed he lied about where he went later that night and whether he had exchanged text messages with the woman. Armstead didn't see it as a lie; he said in his appeal he simply couldn't remember what happened during a night that was two-and-a-half years ago regarding a woman he barely knew.

Although a Title IX investigation is not a criminal process and requires a lower bar of evidence to determine guilt, Texas law states that someone can be guilty of sexual assault if he knowingly has sex with someone who is too intoxicated to give consent.

Waco police's Swanton said he did not know why the officers who spoke with the woman did not pursue a consent investigation that night after detailing in the report that she was "very intoxicated." He said there is no statute of limitations on investigating the 2013 case.

Coaches urged Armstead to opt for a transfer instead of challenging the school's expulsion, "but I stayed because I believed, and still believe, that I would have a fair opportunity to clear my name," he wrote in the appeal. "I am not a barbarian. I didn't do this." He wrote that Title IX officials advised him not to go to the media, after his attorney suggested that "might be the only way I would get a fair hearing."

He stated in his appeal that the entire process was unfair and biased against him from the beginning, noting he was kicked off the team at the start of the investigation, and the adjudicator dismissed any conflicting testimony that favored his side of the story.

Armstead had been on school probation before: for keeping a dog in his room in unsanitary conditions, according to the Title IX report. He also had been named as a suspect in a July 2, 2015, assault, according to a report from Waco police. No charges were filed in that case, and the report, which was not released in its entirety, did not indicate what happened, other than that a woman reported three men arrived at her apartment demanding she bring her boyfriend out to meet them. It's unknown whether Baylor officials were aware of that incident.

Armstead had the opportunity to appeal his expulsion a final time last week, directly to Starr, but declined. His family is considering a lawsuit, according to a representative of Armstead's who spoke only on the condition of anonymity. On April 1, it was announced that Armstead had signed with the Saskatchewan Roughriders of the Canadian Football League.

Although the woman prevailed in the Title IX investigation, she shared some of the same frustrations with the process as Armstead. In addition to the delay in getting the investigation started, she and Armstead say what was supposed to take 60 days took about five months; notifications weren't timely; evidence was presented without time to review or respond; and the final reports contained inaccuracies. One of Baylor's Title IX investigators resigned halfway through the case.

The alleged victim told Outside the Lines, "I just felt like that in that whole Title IX process, they were just so overtaxed they could not do the job that they were supposed to do."