Ok, I was unclear.
Sex assaults are crimes and are investigated by law enforcement. However, Title IX is part of US Federal Civil Rights legislation which forbids discrimination from any educational opportunity on the basis of of sex. This applies, then, to any institution receiving federal financial support (like any school that accepts federal loans or grant as payment).
Under this authority, schools are obligated to ensure that their students don't face threats or diminished educational opportunities because of their sex. Sexual assaults are recognized as having the capability of diminishing those educational opportunities. Accordingly, every school has a "Title IX Compliance" department that, in addition to ensuring correct funding and availability of opportunity, also helps compile and oversee sex crime statistics and administration.
Being arrested, tried, and convicted of sex assault is a matter for the criminal court system and is handled there. That process can result in a person losing their freedom and going to jail. There are long recognized procedures for this, with commensurate standards.
Participating in college athletics is not a right, but merely a privilege. It can be removed or suspended for far less standards than those required for a criminal conviction in a courtroom. For our purposes here, the Title IX Compliance office is a perfect place for assault claims against a player to land. A sports coach is largely removed from the role of having to decide suspensions or sanctions. The Title IX office handles the fact gathering as is pertinent to the University's need to ensure a non-discriminatory environment. The criminal court system handles the prosecution related to the, well, criminal complaint.