Texas Property Code - PROP § 24.004. Jurisdiction;  Dismissal

(a) Except as provided by Subsection (b), a justice court in the precinct in which the real property is located has jurisdiction in an eviction suit.  Eviction suits include forcible entry and detainer and forcible detainer suits.  A justice court has jurisdiction to issue a writ of possession under this chapter.

(b) A justice court does not have jurisdiction in a forcible entry and detainer or forcible detainer suit and shall dismiss the suit if the defendant files a sworn statement alleging the suit is based on a deed executed in violation of Chapter 21A, Business & Commerce Code.

(c) A justice court in which a petition is filed under Section 24.00505 must adjudicate the right to actual possession of the premises.  The justice court may not adjudicate title to the premises.  Counterclaims and the joinder of suits against third parties are not permitted in eviction suits.  This subsection does not preclude a claim that may not be asserted under this subsection from being brought in a separate suit in a court of proper jurisdiction.