A case where the judgement might be lashes requires 3 judges, with an explanation of why, from a verse. So why do others maintain that 23 judges are needed for such a case? In part because of the connection to lashes being linked to a death sentence - though perhaps the seriousness of lashes themselves pushes for that connection. Also, intercalation of a month (to make a leap month) needs 3 judges. The discussion distinguishes between the procedure for establishing the month vs. figuring out that a month needs to be added. Plus, a treatment of the dispute of 3 vs. 5 vs. 7 judges dispute for proclaiming the leap month, and why those numbers.