Find the violation.
A) The freedoms of speech, expression, and assembly are fundamental rights of all persons and are central to the mission of the University. In accordance with this Chapter, students, faculty members, staff members, and Members of the Public have the right to assemble, to speak, and to attempt to attract the attention of others, and corresponding rights to hear the speech of others when they choose to listen, and to ignore the speech of others when they choose not to listen.
Confirms the right we all know the students had.
B) In furtherance of the University’s educational mission, the University buildings including their outside surfaces, surfaces associated with or connected to a University building, and University structures are limited public forums open only to the expressive activities of faculty, staff, and students as set forth in this Chapter. Members of the Public may engage in expressive activities at the University in accordance with the rules contained in this Chapter, including generally applicable or localized "time, place, and manner" rules as described in Subsection 13-304. Student, faculty, and staff organizations may not invite the public at large to events in University buildings or facilities, or locations that are not in a common outdoor area.
The students weren't in the buildings. And, students would be allowed to express themselves there anyway.
C) Students, faculty, and staff members are free to express their views, individually or in organized groups, orally or in writing or by other symbols, on any topic, in all parts of the campus, subject only to rules necessary to preserve the equal rights of others and the other functions of the University. Teaching, research, and other official functions of the University will have priority in allocating the use of space on campus. Members of the Public may engage in expressive activities only in common outdoor areas of the campus, and subject to the time, place, and manner rules necessary to preserve the functions of the University, as set forth in subsection 13-304.
Ok, sounds good so far. I'm not seeing anything violated by the students yet.
D) The University will not discriminate on the basis of the political, religious, philosophical, ideological, or academic viewpoint expressed by any person, either in the enforcement and administration of these rules or otherwise. This subsection does not limit the University's ability to enforce provisions involving prohibited categories of expression described in Subchapter 13-200.
There may be a violation here, but not by the students.
E) The University of Texas at Austin Police Department (UTPD) may immediately enforce these rules if a violation of these rules constitutes a breach of the peace or compromises public safety.
Or may enforce non-existent rules apparently.
I've looked at the rest of rules. They generally suggest that time and place restrictions exist, but don't provide any specific details. There is some specific regulations on amplified speech and exhibits that don't seem relevant here. Oh, there is this:
Sec. 13–901. General Rule on Public Assemblies
“Publicly assemble” and “public assembly” include any gathering of persons, including discussions, rallies, and demonstrations. The rules in Subchapter 13–800 apply to any use of amplified sound at a public assembly.
Persons and organizations may publicly assemble on campus in any place where, at the time of the assembly, the persons assembling are permitted to be. This right to assemble is subject to the rules in this Chapter and to the rules on use of University property in Chapter 10 of the Institutional Rules. No advance permission is required in the common outdoor areas.
Oh... wait... may assemble on campus in any place where the person is permitted to be. Hmm, I don't recall their being a prohibition on students being on the South Mall. So, I guess, you tell me @Frank Drebin, where are students not allowed to be?