Question

why did Hitler create surveillance forces in German beside the regular police

Answer 1

He is a not best ruler he want to make his police officer no one

Answer 2

the original police was known by everyone. But the surveillance forces were a secret squad and performed the function of spies. They would monitor the people and if they find any Jews, they pass the message to the police forces who would come and take them to concentration camps. With the help of the surveillance forces he made his rule even more stronger and firm.