It might be true that the best offense is a good defense in some sports, but when it comes to interpersonal interactions, I'm not so sure that's an effective strategy.
For a variety of reasons, sometimes people verbally attack each other. It happens. It's a rare person who manages to avoid being blamed, accused, or called names at one time or another. And when we feel unjustly accused, it's natural to want to defend ourselves. The only problem is that more often than not, defending ourselves or proclaiming our innocence only escalates the conflict.
For example, let's say you head to the grocery store. You don't even notice that other car waiting there, so you pull right in to a parking space that just opened up, happy to have scored such a sweet spot. As you innocently exit your car, you are immediately confronted by a redfaced, sputtering guy standing way too close to you and yelling way too loud.
How would you react? Depending on your temperament and the kind of day you are having, you may insist that you didn't even see him there, and that it wasn't your fault. You may raise your own voice and tell him to back off. Or you may become too frightened and flustered to utter a syllable.
What you probably won't do, unless you've been trained in some type of conflict resolution, is say, "I can understand why you are angry. If I thought someone stole my parking space, I'd be angry too."
What upset people need most is not correction. They need understanding. And until they get it, they are not likely to be able to hear or accept your version of what happened. Speaking rationally to an upset person is just like talking to the dog. All they hear is blah blah blah.
What turns their ability to listen back on again is acknowledgment: I hear you. I get it. I understand why you would feel that way.
So the next time you are blamed or falsely accused, pause a moment before you set the story straight to acknowledge the feelings or needs of your accuser: You were waiting for the space and I pulled into it. It seemed like I intentionally took your spot. I understand why you are upset.
This kind of response can very quickly defuse aggression. Later, after they've cooled down a bit, would be a more effective time to ask if they are open to hearing your perception of what happened, or find out what it would take to make it right. Sometimes those conversations aren't even necessary, because after they feel heard and acknowledged, they settle down and their perception clears without your input.