Tex. Local Government Code § 89.002

(a) The commissioners court may spend, in the name of the county, money from the county's general fund for membership fees and dues of a nonprofit state association of counties if:

(1) a majority of the court votes to approve membership in the association;

(2) the association exists for the betterment of county government and the benefit of all county officials;

(3) the association is not affiliated with a labor organization;

(4) neither the association nor an employee of the association directly or indirectly influences or attempts to influence the outcome of any legislation pending before the legislature, except that this subdivision does not prevent a person from providing information for a member of the legislature or appearing before a legislative committee at the request of the committee or the member of the legislature; and

(5) neither the association nor an employee of the association directly or indirectly contributes any money, services, or other valuable thing to a political campaign or endorses a candidate or group of candidates for public office.

(b) If any association or organization supported wholly or partly by payments of tax receipts from political subdivisions engages in an activity described by Subsection (a)(4) or (5), a taxpayer of a political subdivision that pays fees or dues to the association or organization is entitled to appropriate injunctive relief to prevent any further activity described by Subsection (a)(4) or (5) or any further payments of fees or dues.