Texas Government Code - GOV'T § 62.020. Alternate Jurors

(a) In district court, the judge may direct that not more than four jurors in addition to the regular jury be called and impaneled to sit as alternate jurors.

(b) In county court, the judge may direct that not more than two jurors in addition to the regular jury be called and impaneled to sit as alternate jurors.

(c) Alternate jurors shall be drawn and selected in the same manner as regular jurors. An alternate juror must meet the same qualifications, is subject to the same examination and challenges, shall take the same oath, has the same functions, powers, and privileges, and shall be accorded the same facilities and security as a regular juror.

(d) In the order in which they are called, alternate jurors shall replace jurors who, prior to the time the jury retires to consider its verdict, become or are found to be unable or disqualified to perform their duties. An alternate juror who does not replace a regular juror shall be discharged after the jury retires to consider its verdict.

(e) Each side is entitled to one peremptory challenge in addition to those otherwise allowed by law or by rule if one or two alternate jurors are to be impaneled. Each side is entitled to two peremptory challenges in addition to those otherwise allowed by law or by rule if three or four alternate jurors are to be impaneled. The additional peremptory challenges may be used against an alternate juror only, and the other peremptory challenges allowed by law or by rule may not be used against an alternate juror.