[If] one was sentenced and fled, and then came before that very same court, they do not overturn his sentence. Wherever two stand up and declare, “We testify concerning so-and-so that he was sentenced in so-and-so's court, and so-and-so and so-and-so were his witnesses,” he is executed. A sanhedrin functions both in the Holy Land and outside the Holy Land. A sanhedrin that executes once in a septenary is called a destroyer. R' Elazar ben Azariah says: Once in seventy years. R' Tarfon and R' Akiva say: Had we been on a san-hedrin, a person would never have been executed. Rabban Shimon ben Gamliel says: They too would have increased [the number of] murderers in Israel.