Bigby v. State
In Bigby v. State 892 S.W.2d 864, 891 (Tex.Crim.App. 1994), five members of the Court expressed their belief that the fairest and most objective interpretation of Article 35.13 provides trial judges the discretion during voir dire "to permit the exercise of challenges for cause by both sides before moving on to any use of peremptory challenges."
In other words, a trial court has the discretion to decide:
(1) whether the State must voice both a challenge for cause or a peremptory challenge before the defendant, or;
(2) that both sides issue any challenges for cause before the State first lodges a peremptory challenge.
The latter method appears to be what both the trial court and the State assumed was being followed.
Defense counsel, on the other hand, assumed the alternative.
Either method, however, is acceptable under Article 35.13, and no error can result if either is followed.