Adam Clarke on Deuteronomy 16:18

Judges and officers shalt thou make - Judges, שפטים shophetim, among the Hebrews, were probably the same as our magistrates or justices of the peace. Officers, שטרים shoterim, seem to have been the same as our inquest sergeants, beadles, etc., whose office it was to go into the houses, shops, etc., and examine weights, measures, and the civil conduct of the people. When they found any thing amiss, they brought the person offending before the magistrate, and he was punished by the officer on the spot. They seem also to have acted as heralds in the army, Deu 20:5. See also Rab. Maimon in Sanhedrin. In China, for all minor offenses, the person when found guilty is punished on the spot, in the presence of the magistrate or mandarin of justice.