The subjective state of your mind is not a critical element. ... You're going to be judged first and foremost by your actions, so make sure they comport precisely with the law.
In TX, the subjective state of the defender's mind must be considered if one is to "comport precisely with the law".
That is, one is not complying precisely with the law, regardless of the actions taken, if the person's mindset at the time of the incident does not fit the model plainly set forth in the law.
One can certainly argue that it's not possible for the justice system to know what's going on in one's mind, but that's a secondary issue. If one's goal is to comply with the law (comport precisely with the law, if you will) then it's not possible to dismiss the subjective state of mind of the defender.
From the TX penal code preceding the section on the legal use of force and deadly force:
The use of deadly force is not justified under this section unless the actor reasonably believes the deadly force is specifically required by statute...
From the TX penal code regarding the legal use of force:
...a person is justified in using force against another when and to the degree the actor reasonably believes...
From the TX penal code regarding the legal use of deadly force:
A person is justified in using deadly force against another: (1) if the actor would be justified in using force against the other under Section 9.31; and(2) when and to the degree the actor reasonably believes...
Note that in all cases, the primary stipulation that the defender must satisfy is that he must have the proper state of mind; i.e. he must have the
reasonable belief that deadly force is required and the
reasonable belief that it is immediately necessary and then he must use it only to the degree that he
reasonably believes is necessary.
It's true that the Castle Doctrine provides that PRESUMPTION of reasonable belief exists if the Castle Doctrine criteria are satisfied. What many don't understand, or don't want to understand is that it's possible for the defender to destroy that presumption by providing evidence against himself in the form of public statements that make it clear his subjective mind set was NOT, in fact, in compliance with the letter of the law.
For example, let's say a person were to state publicly that he was going to kill any intruder in his house, regardless of the circumstances, and then later was involved in a shooting inside his house where the intruder died.
Had he kept his mouth shut and assuming that the Castle Doctrine criteria were satisfied, the presumption would have AUTOMATICALLY existed that he acted out of a reasonable belief that deadly force was immediately necessary and that he only used deadly force to the degree that he reasonably believed was necessary. The state, in order to successfully convict, would have to PROVE that he didn't have the right state of mind. A very difficult task by any standards.
HOWEVER, his prior public statements that he was going to kill any intruder in his house regardless of the circumstances would be VERY damaging to that presumption and could be used by the state to demonstrate that he acted based on a pre-conceived strategy which had nothing to do with the actual circumstances of the situation or his reasonable belief of what was necessary at the time. In other words, his ill-advised public statement has destroyed, or at least significantly weakened a presumption of justification that would have existed had he not made such statements.
Now he'll have to prove what the law would have formerly been required to presume was true, and even worse, the evidence against him is of his own making. He'll have to prove that what he said before should be disregarded but that what he's saying now is the truth. Why would anyone want to put himself in that situation? Especially since the the only cost of avoiding the situation is merely not making ill-advised comments in public/online.