SAN JOSE — Citing insufficient evidence, prosecutors have decided not to file charges against a San Jose State water polo player accused of sexually assaulting two female student-athletes in a case that led to changes in how the college handles rape allegations.

Two San Jose State students came forward in September to report that an international freshman water polo player had raped them at an off-campus house party over Labor Day weekend, just months after a sexual assault case involving former Stanford swimmer Brock Turner triggered a flood of outrage.

But after a months-long, “comprehensive investigation,” senior prosecutors concluded that charges were not warranted because of “conflicting statements, a lack of corroborating evidence and other insurmountable legal issues,” according to a written statement by Assistant District Attorney Terry Harman.

“This decision in no way endorses the boorish behavior by the male student,” Harman wrote. “Nor does this decision reflect the slightest wavering in our determination to fight the epidemic of campus sexual assaults and to prosecute them to the fullest extent of the law.“

However, the student-athlete could still face sanctions, including expulsion, under the university’s anti-discrimination or Title IX process.

The water polo player could not be reached for comment Tuesday. But his lawyer commended prosecutors and San Jose police for their effort to “do the right thing.”

“It takes a lot of courage not to prosecute,” lawyer William J. Portanova said. “These are extremely difficult cases.”

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Neither of the women who reported being assaulted could be reached for comment.

But activists with the survivor-advocacy group End Rape on Campus said false reports of sexual assault are extremely rare.

Yet only 14 to 18 percent of all sexual assaults nationwide that are reported to police are prosecuted, according to a 2011 study by the University of Kentucky Center for Research on Violence Against Women. In contrast, the Santa Clara County District Attorney’s Office in 2016 prosecuted about 57 percent of sexual assault cases that were reported to police, which the executive director of the End Rape on Campus group said is better but still not adequate.

“We still live in a world where many people believe the woman could have prevented sexual assault,” executive director Annie E. Clark said. “How short was her skirt? How much did she have to drink? Why did she go into the room with him?”

In mid-October, one of the women described in an interview with the Bay Area News Group a chilling account of texting “Help me” to the first person who popped up on her phone after she said she was cornered in a dark bedroom by the athlete, thrown down and attacked until she could escape. This news organization is not naming the student-athlete because he has not been publicly identified or formally accused of a crime. The university and the student’s lawyer would not say what country he’s from, and it was unclear whether he’s still in the U.S.

The university temporarily suspended the student-athlete in late-September, barring him from entering campus property or participating in any campus-related activities, including team practices. He will remain temporarily suspended while the Title IX investigation continues. “The criminal case has no bearing whatsoever on a Title IX investigation,” said Natalie Brouwer Potts, the college’s Title IX officer. “One of the very big differences is that the standard of proof in a criminal case is ‘beyond a reasonable doubt,’ while in a Title IX investigation, it’s ‘preponderance of the evidence,’ meaning it’s more likely than not” that the violation occurred.

The first allegation against the international student-athlete came to light on Sept. 4. The second woman came forward about two weeks later, and on Sept. 22, San Jose State issued the interim suspension.

When news of the alleged assaults surfaced, some students questioned why the university had not issued a crime alert. One of the women who reported the alleged assault also said she had received scant information about the investigation from the university and learned much of what she knew from news reports.

In October, university President Mary Papazian pledged to change how the campus responds to sexual assaults and treats women. Since then, the college has issued at least one campus alert about an allegation of sexual battery, a legal term for unwanted touching. Potts, who was hired in October, also is responsible for maintaining good communication with alleged victims.

The president also promised to facilitate a series of campus-wide conversations on identifying and combating sexual violence and harassment. Potts said she has held two meetings so far, including one in the student union that drew about 100 people. Another public meeting is set for Feb. 14.

The Santa Clara County District Attorney’s Office in 2016 prosecuted about 57 percent of sexual assault cases that were reported to police. In contrast, only 14 to 18 percent of all sexual assaults nationwide that are reported to police are prosecuted, according to a 2011 study by the University of Kentucky Center for Research on Violence Against Women.

947: Number of sexual assault cases reviewed in 2016 by Santa Clara County District Attorney’s Office

542: Cases filed

402: Cases rejected

3: Cases still under review at the end of the year