Untitled Texas Attorney General Opinion, KP-0125

In May 2016 one person was elected both to the City of Forest Hill council and to the Forest Hill Public Library District board; the District lies within the City's territorial limits.
Forest Hill council members receive no compensation under the city charter; library district trustees are elected and exercise governmental powers (including borrowing, land acquisition, and taxation-related powers).
Article XVI, § 40 of the Texas Constitution forbids simultaneously holding more than one "office of emolument"; an "emolument" is compensation for the office.
The Attorney General examined both the constitutional ban and the common-law doctrine of incompatibility (self-appointment, self-employment, conflicting loyalties), focusing here on conflicting loyalties.
Both the city council seat and the library district trusteeship are "offices" for incompatibility analysis because they carry sovereign functions and are exercised independently by elected officials.
Both the City and the Library District have taxing authority (including sales-and-use taxes), and their jurisdictions overlap, creating direct competition over limited tax rates.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether Art. XVI, § 40 (dual offices of emolument) bars dual service	The dual positions are both offices of emolument and thus prohibited	City council receives no compensation, so at least one position is not an office of emolument	Not barred by Art. XVI, § 40 because the city council position is unpaid (not an office of emolument)
Whether common-law incompatibility (conflicting loyalties) permits dual service	Dual service is permissible	Overlapping taxing authority creates competing loyalties that impede independent judgment	Offices are incompatible due to overlapping taxation power; dual service prohibited
Effect of qualifying for the second office after already taking the first	The official retains first office	Qualifying for a second incompatible office constitutes an automatic resignation from the first	Qualifying and accepting the second incompatible office vacates the first office automatically

Thomas v. Abernathy County Line Indep. Sch. Dist., 290 S.W. 152 (Tex. Comm'n App. 1927) (recognizing incompatibility where municipal and school trustee duties may conflict)
Pruitt v. Glen Rose Indep. Sch. Dist., 84 S.W.2d 1004 (Tex. 1935) (holding qualification for a second incompatible office operates as resignation from the first)
State ex rel. Hill v. Pirtle, 887 S.W.2d 921 (Tex. Crim. App. 1994) (discussing standard for incompatibility and scope of Art. XVI, § 40)
Aldine Indep. Sch. Dist. v. Standley, 280 S.W.2d 578 (Tex. 1955) (defining an "officer" as one exercising sovereign functions independently)