Gestapo

The Gestapo was the state police and intelligence agency of Germany during the Nazi era of 1933 to 1945. They were considered one of the most feared and ruthless such organizations in Earth history.

James Kirk questioned Melody Sawyer's decision to follow the orders of her AreoNav superiors unquestioningly to the behavior of the Gestapo, as well as to the troops serving under Colonel Green. 

Federation historian John Gill created a Gestapo, along with a National Socialist government, on planet Ekos in the mid 2260s. 

Gestapo officers played a role in a USS Voyager holodeck program set in France, 1944. 

Alternate universes
During his accidental visit to the "mirror universe," Commander Montgomery Scott compared security aboard the, under the command of $𝜇$, to the Gestapo. 

In another alternate timeline, Gestapo officers searched the streets of 1944 Brooklyn for Captain Jonathan Archer, going house-to-house and shooting people at random.