Acts 16:37. They have beaten us openly uncondemned, being Romans, and have cast us into prison.
The treatment of these prisoners, being Roman citizens, was illegal in three different ways: 1. In binding them in the stocks. 2. In beating them. 3. In failing to give them a trial. The Valerial law forbade the binding of a Roman citizen. The Porcian law forbade his being beaten. Cicero, in his celebrated Oration against Verres, asserts that “it is a transgression of the law to bind a Roman citizen; it is wickedness to scourge him. Unheard, no man can be condemned.”
This will account for the fear expressed by the magistrates when they heard that the prisoners were Romans. See verse 38. Paul had a similar experience afterward in Jerusalem: “As they bound him with thongs, Paul said unto the centurion that stood by, Is it lawful for you to scourge a man that is a Roman, and uncondemned” (Acts 22:25).