I watched a great video a few years back by a criminal defense attorney speaking on this topic. He proved that there is literally nothing you can say to the police that will help you in any way. Any and all information you give to the police will only be used to build a case against you. The scene speaks for itself. If the prosecution decides to prosecute you based on an erroneous interpretation of the evidence, it is not your expertise to contradict the interpretation. That is your attorney's job. You will do nothing but screw yourself over and weaken your defense. Keep your mouth shut. I'm paraphrasing, but here is the jist of what he recommended:
If you are in fear for your life, there is no choice but to shoot until the threat is no longer a threat. Dial 911, but do not answer whatever questions the dispatcher is asking.
1. My name is (your name) and I just shot an intruder in my home because I was in fear for my life and that of my family.
2. The intruder is down. everyone else is safe. Please dispatch emergency personnel immediately to (your address).
3. Please advise the police that I am a (brief description of yourself) and that I am placing the gun down away from my person. My (other family members) are here and I will have them wait (safe location in the home). Everyone is unarmed and safe.
At this point, the dispatcher is going to try and get you to elaborate. Do not give any more information for any reason. Politely tell him/her that you are hanging up now and will wait for the police to arrive, and thank them for their help. If you don't want to hang up, answer any of her questions with, "I wish I could be more helpful, but I will need to speak with my attorney before saying anything further."
When the police arrive, here is the information the police require:
1. Tell them who you are, where the rest of your family is, and that no one else is injured.
2. Tell them where the perp is, if it isn't obvious.
3. Tell them where the firearm is.
4. Tell them you feared for your life and that of your family.
It does not matter what information the cops are asking for, or any other questions they might have. Give them the above information, and the above information only. Do not give any other information for any reason.
The police will continue to ask questions, and pressure you to elaborate. Reply to any and all of their questions with "I wish I could be more helpful, but I will need to speak with my attorney before saying anything further." It doesn't matter how many additional questions the cops ask, just respond to each one with the exact same phrase. They will get the message. Also... you are going downtown. Whether you are smart, and keep your mouth shut, or you try and talk the cops heads off about how you're a law abiding citizen to keep from going downtown.
Make sure your family knows this as well. Drill and practice the police interrogation scenario with them, because you will not be in a state of mind to think on your feet if you end up in this situation. Never, EVER speak to the police. Your attorney is your voice.