Please report this to your union!
The law that guarantees university employees the right to organize collectively, represent each other and/or form unions is called the Higher Education Employee-Employer Relations Act (HEERA). Employees have a right (even across bargaining unit lines) to talk about matters related to representation and unions. It is very important that you report to your union reps and/or stewards any instances of interference with the rights of employees to talk about matters such as unions, representation, grievances and/or the right of employees to file them.
According to Article 3571 of HEERA it is an unfair labor practice (ULP) for the university to interfere:
3571. It shall be unlawful for the higher education employer to do any of the following:
(a) Impose or threaten to impose reprisals on employees, to discriminate or threaten to discriminate against employees, or otherwise to interfere with, restrain, or coerce employees because of their exercise of rights guaranteed by this chapter. For purposes of this subdivision, "employee" includes an applicant for employment or reemployment.
(b) Deny to employee organizations rights guaranteed to them by this chapter.
(c) Refuse or fail to engage in meeting and conferring with an exclusive representative.
(d) Dominate or interfere with the formation or administration of any employee organization, or contribute financial or other support to it, or in any way encourage employees to join any organization in preference to another. However, subject to rules and regulations adopted by the board pursuant to Section 3563, an employer shall not be prohibited from permitting employees to engage in meeting and conferring or consulting during working hours without loss of pay or benefits.
(e) Refuse to participate in good faith in the impasse procedure set forth in Article 9 (commencing with Section 3590).
(f) Consult with any academic, professional, or staff advisory group on any matter within the scope of representation for employees who are represented by an exclusive representative, or for whom an employee organization has filed a request for recognition or certification as an exclusive representative until such time as the request is withdrawn or an election has been held in which "no representative" received a majority of the votes cast. This subdivision is not intended to diminish the prohibition of unfair practices contained in subdivision (d). For the purposes of this subdivision, the term "academic" shall not be deemed to include the academic senates.