In a totalitarian state, what is the main function of the secret police?

 To create fear among people and create obedient subjects who will blindly follow the regime

Explanation:  Secret police is one of the most important levers of totalitarian regimes. The basic task of the secret police is to protect the absolutist rule of the dictator, and it does so in a variety of violent ways. This, of course, involves acts that are not in accordance with the law for the elimination of political opponents, and even those who are suspected of being against the regime. This creates fear among people and makes them obedient.

the revolution instituted a short-lived roman republic.