Texas Local Government Code - LOC GOV'T § 150.002. Political Activities

(a) While in uniform or on active duty, an employee of the fire or police department of the municipality may not engage in a political activity relating to a campaign for an elective office.

(b) For the purposes of this section, a person engages in a political activity if the person:

(c) While out of uniform and not on active duty, an employee of the fire or police department may engage in a political activity relating to a campaign for an elective office, including each activity listed by Subsection (b), except that the person may not solicit campaign contributions for a candidate other than from members of an employee organization to which that person belongs.