The Hell Bunny has it locked.
In Texas we have the Castle Law. You can shoot a person in your own home for almost any reason. You cannot, however, carry a pistol to a motel and shoot someone there.
The secret is, when asked by the police, say "I was in fear for my life." It's a get out of jail free card in Texas. If you have a concealed carry that may work somewhere else but it always works at your home because you may go armed at home any time you choose.
Shooter1a, you are wrong! Read the castle doctrine which is codified at Texas Penal Code 9.31. Specifically, 9.31(a)(3) states that deadly force is justified in cases in which the shooter 1. Has a reasonable fear for their life 2. and
is not engaged in criminal activity at the time of the shooting, with the exception of a Class C misdemeanor or traffic violation (i.e. speeding). If a John is at the lady's house, they're doing more than talking. If and when she lies about why he was there, then it will just open a whole can of worms.
Investigators will subpoena computer records, cell phone/Text message logs, maybe even look to this site if they find it on one of their computers. If and when it is shown that he was hitting her up for some sex-for-hire, a Class B misdemeanor in Texas, you have a problem! It's not to say it can't be used, but engaging in criminal activity defeats/eliminates the presumption of justification for the shooter.
Also, if you're a convicted felon in Texas (that can come from multiple prostitution arrests, drugs, violence, etc.) you are precluded from owning any firearm and the "Castle Doctrine" is a moot point. In Krajcovic v. State, the assailant was initially held to be unjustified in the use of deadly force when a drug buyer robbed him. Why? Because Krajcovic was a thug, doing thug shit, and the law doesn't protect you!
Now, he was granted a new trial (there was an error in jury instructions and some evidence was improperly obtained) so he may get off the second time around, but considering he got 55 years for the first killing, it goes to show that you are NOT automatically protected.