"Common sense" is not much more than a myth now that (many, including those of the majority of the posters here) societies are not homogenous and not filled with people all subscribing to a very narrow view of what is right and wrong. I believe "common sense" is, in this context, a way of stating a belief without feeling that any evidence is required. A bit like religion.
There was a thread around here somewhere in which the correct, acceptable behaviour of a society (real, not an imaginary example, unless I radically misread it) involved boys becoming men by giving oral sex (and swallowing) to older men. A neighbouring society decided anal sex was the way to go. This is simply "common sense" in those societies. Everyone agrees.
We live in societies where one person's "common sense" is another person's completely unacceptable behaviour.
"Who would you rather see in court first mass murderer or a thief?"
Will you be petitioning the courts to refuse to try thieves unless everyone accused of murder has been tried already? That would essentially legalise theft.