Tex. Human Resources Code § 40.061

(a) A department employee, a member of a multidisciplinary team established under Section 40.0524, or an authorized department volunteer who performs a departmental duty or responsibility is immune from civil or criminal liability for any act or omission that relates to the duty or responsibility if the person acted in good faith and within the scope of the person's authority.

(b) In this section, "volunteer" means a person who:

(1) renders services for or on behalf of the department under the supervision of a department employee; and

(2) does not receive compensation that exceeds the authorized expenses the person incurs in rendering those services.

(c) This section does not provide immunity to a department employee who, in a suit affecting the parent-child relationship in which child abuse is alleged or that arises out of a child abuse investigation, in a criminal prosecution for an offense in which child abuse is an element, or in the preparation of the suit or prosecution:

(1) commits or attempts to commit perjury;

(2) fabricates or attempts to fabricate evidence;

(3) knowingly conceals or intentionally withholds information that would establish that a person alleged to have committed child abuse did not commit child abuse; or

(4) violates state or federal law in the investigation or prosecution of the suit.