Reference for Sanhedrin 172:17

ואם לאו באין להן לאותן שעל פתח עזרה ואומר כך דרשתי וכך דרשו חבירי כך לימדתי וכך לימדו חבירי אם שמעו אמר להם

— It is necessary [to state this] only if witnesses [of abduction] subsequently appeared.<span class="x" onmousemove="('comment',' And on the combined testimonies the accused was convicted. Yet, if the first witnesses of the sale were falsified, they are not punished, since they can plead: 'we did not know that others would testify to the kidnapping.' ');">¹⁵</span>

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