I don't see how that cite provided helps your claim, especially when a court in your state has ruled that a citizen can perform law enforcement duties and have the same protection as them...
^^^
earlier:
You misread that court case. A citizen can only be called up to aid the civil power by a "constable" who has the authority to "deputize." That case was about CCW and the defendant using his
posse member status to invoke a exception to the CCW statute for constables that the court found he was not lawfully permitted to invoke. That court case is a case of a LAC being railroaded by the system because he listened to a cop instead of knowing the law. This point was raised in that court opinion.
If I am duly sworn and deputized, buy a constable with the authority to "call me to aid the civil power," I can claim the exception to the statute for CCW and I then am subject to RSMo 563.046, LEO use of force, if I am required by circumstance to use force. I am also subject to other statutes that apply to cops, namely arrest powers.
If I am not duly sworn and deputized then RSMo 563.031 applies to me, a more restrictive (higher) standard to meet for the use of force. I can use force but I have a greater burden to prove that my use of force was justified. I can affect an "arrest" (RSMo 563.031.4) but the RSMO does not provide me the leeway that a cop has to affect a arrest.
I suspect, though I do not know precisely, that Texas and Florida have similar statutes that define the authority of a cop, and the "authority" of a citizen and when a citizen can invoke specific cop authorities.