I was a cop for many years, and I must take exception your generalization. I think I do have some native intellect and the ability to discern and discriminate facts. True, we are not friend or ally, especially in the beginning. That takes time and investigation and gathering of information.
You are correct, that even if you cooperate, that is no guarantee that you won’t be arrested and charged. There are regrettably over-zealous cops and prosecutors all over. But in most cases, certainly the ones I was involved in, people who were defending themselves, especially in the sanctity of their homes, are not. There are exceptions, mostly where you have doctrinaire liberals running the show. If you live in such a place, I recommend moving somewhere else more conservative.
But this is why I do concur that the less you say before getting a lawyer, the better. My officers who got involved in duty-related shootings got counsel before going into details. I have no problem with that, nor if a private citizen does. I am in no hurry to make an arrest, especially if I don’t have reason to believe that there is a continuing threat to the citizenry. I can and will take my time to understand what happened and get it right. But very often, the physical evidence and circumstances paint an ambiguous or incomplete picture of the incident. That is where I need to have the party(ies) fill me in on what happened, what they perceived was happening and how they felt at the time. The elements of culpability are all somewhat subjective (Intentionally, Knowingly, Recklessly, Negligently). They sometimes can be inferred from the evidence and circumstances and sometimes they are best established by the statements of the people involved. This can be for good or ill.
Something never to say: “The gun just went off.” Really? Then you didn’t shoot that guy because you were in fear for your life, but rather because you mishandled your firearm? Another - say there are multiple actors. Maybe the one you shot wasn’t the one who was armed, but he was the first one in through your door - the other guy ran away. Think that’s important for the investigator to know? You saw that the actor had some type of edged weapon in his hand? Maybe I’ll take anther look at the discarded screwdriver lying under the tool bench in the garage where the action took place and see if it has the bad guys’ prints or DNA on it. Yes, some of this can come from your lawyer, without you having to make a (potentially incriminating) statement. But your lawyer’s statements aren’t what are admissable in court, they aren’t evidence. If you want something on the record, you will need to be the one to say it. And if you are ‘clean’ you ARE going to want to be on the record at some point.
Help me out here, throw me a bone. After all, I’m pretty stupid, really, and it would be helpful if you’d point out the exculpatory evidence that would go in your favor.
That is a good exception to the rule about clamming up. If the perp shot at you, point out where the bullet likely went so forensics can find it. If he had a weapon, leave it where it fell, do not disturb the prints, and point it out to the police. Beyond that, I'm going to be fairly untalkative.