There isn't anything that you can say at the time you are involved in a shooting that you can't say just as effectively later after having consulted with an attorney.
One common emotional response to surviving a shooting is exhilaration at having defeated an enemy in deadly combat. This emotional response can be mistaken for an unhealthy desire to engage in such combat.
The guy in Pasadena, Texas made a mistake in saying, I believe, something along the lines of "I'll kill them", about the two thieves he was about to confront. No matter how justified the shooting might have been at the instant it occurred, the statement made works against giving the shooter the benefit of any doubt.
Best to just say nothing.
I had two CCW classes from different instructors (first one mandatory for the license and the second one mandatory for the renewal) and in both classes one of the primary focus of the class was the legal aspect every single person who ever has to use their firearm in self defense is going to have to face.
And in both classes the instructors emphasized the importance of never, ever willingly answer any questions on scene after an occurance. The only response you should ever give is that you refuse to answer any questions until you have consulted with your attorney.
This is for your protection because no matter how innocent you may be in whatever has occured, you just might have a local prosecuting attorney such as Mike Nifong.........