I understand where you're coming from. That would be how I feel too if I know conclusively with evidence that the accused person is guilty. It's a sensitive hypothetical situation.

But it wouldn't be ideal for society if everyone acts on everything solely based on their emotions. It would be chaos and barbarism.

That's why we establish a set of morals, laws and ethics that is common to all, to avoid such hypotheticals, to create a social order that protects people's natural rights, and establish ways to deal with those who violate them.