Firing a warning shot either into the air or into the dirt in front of the suspect? Never.
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Says who?
If you're on a ranch in the middle of nowhere in TX, go for it. But if you live in an incorporated area, your Texas state law and city or county ordinances say 'no.' (Texas Penal Code Section 42.12 plus local ordinances of whatever city or town you're in.)
But then Texas is the only state that allows one to shoot at a fleeing felon if the felon is making off with property in the nighttime (Texas Penal Code Section 9.42(2)(B) but you can't shoot during the daytime!)