Tex. Code of Criminal Procedure § 38.49

(a) A party to a criminal case who wrongfully procures the unavailability of a witness or prospective witness:

(1) may not benefit from the wrongdoing by depriving the trier of fact of relevant evidence and testimony; and

(2) forfeits the party's right to object to the admissibility of evidence or statements based on the unavailability of the witness as provided by this article through forfeiture by wrongdoing.

(b) Evidence and statements related to a party that has engaged or acquiesced in wrongdoing that was intended to, and did, procure the unavailability of a witness or prospective witness are admissible and may be used by the offering party to make a showing of forfeiture by wrongdoing under this article, subject to Subsection (c).

(c) In determining the admissibility of the evidence or statements described by Subsection (b), the court shall determine, out of the presence of the jury, whether forfeiture by wrongdoing occurred by a preponderance of the evidence. If practicable, the court shall make the determination under this subsection before trial using the procedures under Article 28.01 of this code and Rule 104, Texas Rules of Evidence.

(d) The party offering the evidence or statements described by Subsection (b) is not required to show that:

(1) the actor's sole intent was to wrongfully cause the witness's or prospective witness's unavailability;

(2) the actions of the actor constituted a criminal offense; or

(3) any statements offered are reliable.

(e) A conviction for an offense under Section 36.05 or 36.06(a), Penal Code, creates a presumption of forfeiture by wrongdoing under this article.

(f) Rule 403, Texas Rules of Evidence, applies to this article. This article does not permit the presentation of character evidence that would otherwise be inadmissible under the Texas Rules of Evidence or other applicable law.