The 282nd prohibition is that a judge is forbidden from following majority rule [in a capital case] if there is only a majority of one. This means that if judges disagree regarding a transgressor — some saying that he should be executed and others saying that he should not, and those saying guilty are a majority of one — it is forbidden to execute him. G‑d has forbidden the judge from executing him until there is a majority of two.

The source of this prohibition is G‑d's statement,1 "Do not follow the majority to do evil." This means, "Do not follow just any majority in a capital case," which is the intention of the phrase "to do evil." In the words of the Mechilta, "If 11 judges rule he is innocent and 12 judges that he is guilty, I would think that he is guilty. The Torah therefore says, 'Do not follow the majority to do evil.' " It is also written there, "You can rule in his favor with a majority of one, and against him with a majority of two."

The details of this mitzvah are explained in the 4th chapter of tractate Sanhedrin.