How we change what others think, feel, believe and do
When accused of something, fight back. Do not naively accept responsibility. Show that you are very unhappy at being thought to be the wrong-doer. Things you can do include:
If you can create an argument, keep it going for as long as possible until the other person gives up.
Why do you always think it's me? You're so biased! Can't you think of others? What about Tom?
That's a very poor argument. Can't you do any better?
Yes. I know that I did it. So what? Is it such a big deal? Picky, picky, picky.
The underlying purpose of the counterattack is to take the topic of conversation off you and onto other things, such as other people and relationships.
A common message in a counter-attack is that the other person is being unfair and may have a personal bias or grudge against you.
When you are personally attacked, this is the 'attack the person' fallacy, which can be a central plank of your counter-attack (which, paradoxically, may use the same method).
Attacking back is sometimes called the 'tiger response'. The principle is that the other person discovers that it is dangerous to accuse you and thinks twice before doing so again in the future.