I wondered how historically likely the mob violence described in John 8 of the New Testament is considered to be. In short, a woman was caught in adultery and is about to be stoned to death. 1) I believe only the Roman government could execute someone so wouldn't this be illegal? 2) By this time hadn't Judaism created legal loopholes until capital punishment was almost nonexistent? 3) Would the Roman and Jewish leadership turn a blind eye to honor killings like this or would they try to intercede?
I can't address the plausibility of the scenario in 1st century Judaea, but it is probably worth my pointing out that the passage is not authentic. It simply does not appear in the vast majority of Greek manuscripts. Here's the critical note in the standard Nestle-Aland critical edition, where each letter and each number in roman type represents a manuscript (listed at the back of the edition).
The episode is present in only four 1st millennium Greek manuscripts - the codex Bezae (5th cent.), the codex Cyprius (9th cent.), and another 9th century manuscript - and absent in 22, including all the earliest ones, namely papyrus 66 (ca. 200), papyrus 75 (3rd cent.), and the codex Sinaiticus (4th cent.). No Syriac manuscripts include the episode. In addition, the episode is stylometrically distinct from the rest of John.
Its introduction into the modern text is apparently a result of its popularity in the Latin manuscript tradition, that is, texts of the New Testament translated from Greek into Latin. The story is mentioned by two 4th century Latin sources (Pacian and 'Ambrosiaster'), and is present in most Latin copies of John.
I've seen some suggestion that the episode may have been copied from a lost non-canonical gospel, but I can't evaluate that idea myself. My point is, I'd be wary of expecting any authenticity in the story, when we know for certain that there's no authenticity to the text. That said, it's imaginable that the story might nonetheless be feasible - but as I said at the start, I'm not the person to address that.