In order to deter slaves from escaping and free citizens from aiding in escape attempts, legislation was passed in Congress by southern congressmen. These laws stipulated that it was illegal for any citizen to assist an escaped slave. Furthermore, the legislation, which was entitled The Fugitive Slave Act (1850) demanded that if an escaped slave was sighted, he or she should be apprehended and turned in to the authorities for deportation back to the "rightful" owner down south. It was thought that the Fugitive Slave Act would diminish the incentive for slaves to attempt escape. The rationale behind this was the slaves' realization that even if they managed to escape from their plantation, they could still be caught and returned by any citizen in the United States. In fact, the Fugitive Slave Act was so severe that at the behest of Senator Henry Clay, it was legislated that any United States Marshall who refused to return a runaway slave would pay a hefty penalty of $1,000.