By August 1934 Hitler was a dictator with absolute power. In order to maintain this power he needed organisations that could control the population to ensure absolute loyalty to the Führer. After the demise of the SA on the Night of the Long Knives, there were three main interlinked organisations (in addition to the regular German police force) involved in controlling the German people through spying, intimidation and if necessary, imprisonment.
A good mnemonic to help you remember some of the key features of this topic is:
The Nazis quickly swept away many of the freedoms that Germans had enjoyed under the Weimar constitution. The party’s control of the legal system made opposition to the regime very difficult indeed.
These changes more than halved the number of criminal offences between 1933 and 1939, whilst the number of crimes that carried the death penalty increased from three to 46. Many convicted criminals were not released at the end of their sentences but instead were moved to the growing number of concentration camps being established by the SS.
The first camp to open was at Dachau, just outside Munich, in 1933. Soon there were others including Buchenwald, Mauthausen and Sachsenhausen. They were explained as places to detain enemies of the state. They were "concentrated" in one place for political re-education.
Prisoners wore a coloured triangle which identified their crime:
Life in the concentration camps was extremely harsh. Prisoners were made to live and work in horrendous conditions.
When reports of prisoners' experiences leaked out, it increased the fear of being arrested. This fear helped the Nazis keep control.