No, it doesn't follow criminal law. It's internal, but the student is assured due process. The student is investigated to ascertain if facts and evidence support a violation of the UT Standards of Conduct and if the case investigators conclude that there is evidence of a violation, then sanctions, from a warning to explusion, are recommended and enforced. The student has rights, is entitled to an advocate, can present his own case and witnesses and challenge the allegations against him.
If a witness lies or misrepresents what s/he saw or heard, s/he can be found in violation and subject to his/her own midsconduct investigation. Which is why witnesses so often walk back their allegations. The next time they're questioned, they're often fuzzy on the details and unwilling to stand by what they said in the heat of the moment. The second they admit they're not 100% sure or indicate they could have been mistaken, the case crumbles.