TT #258 · Parashas Shoftim · Sixth Aliyah · Passuk 19:19
Then you shall do to him as he had plotted to do to his brother, and you shall purge the evil from your midst.
Torah Temimah points to Makkot 5b.
TT lemma: כַּאֲשֶׁר זָמַם.
English: ‘As he had plotted’ – money for money, lashes for lashes, death for death.
Derash on reciprocal penalty (Bavli) — the punishment matches the intended harm in category.
The court imposes on the zomemim the same category of penalty they sought to impose: monetary, corporal, or capital.