Texas Code of Criminal Procedure - CRIM P Art. § 45A.151. Defendant's Plea

(a) A pleading of a defendant in a justice or municipal court may be oral or in writing as directed by the court.

(b) After a jury is impaneled, or after the defendant has waived trial by jury, the defendant may enter:

(c) If a defendant is detained in jail before trial, the justice or judge may permit the defendant to enter any of the pleas described by Subsection (b).

(d) If a defendant is charged with an offense involving family violence, as defined by Section 71.004, Family Code, the justice or judge must take the defendant's plea in open court.