Texas Government Code - GOV'T § 3100.067. Carrying in Procession With Other Flags

(a) If the state flag is carried in a procession with another flag, other than the flag of the United States, the state flag should be on the marching right. If there is a line of other flags in the procession, the state flag should be in front of the center of that line.

(b) If the flag of the United States is carried in a procession with the state flag, the flag of the United States should be on the marching right.