Helga Grabitz and her husband, Wolfgang Scheffler, were the two preeminent figures in the prosecution of Karl Streibel, commandant of the Trawniki SS Training Camp, in District Lublin, Government-General (Poland). The Hamburg trial resulted in an acquital for Streibel of "base motive murder" (a charge that is very hard to prove under German law).
Grabitz was the chief prosecutor at Streibel's trial, and Scheffler was the most important historical witness to give testimony about "Reinhard" and the Trawniki system. (THe training camp had, by 1942, an attached Jewish forced labor camp that produced as an SS's economic enterprise.)
This work has the strengths and flaws one might expect: an intimate sense of the the fate of the Jews of the GG as the wheels of annihilation turned, less certainty about what exactlly the Trawniki camp and its operation signified (beyond the labor camp side), and a somewhat looser accounting for sources than a specialist might otherwise like.
The Streibel case was build almost exclusively on the testimony of witnesses -- survivors and perpetrators, alike. The voluminous surviving wartime documentation from Trawniki, held by the KGB and stored in Lubyanka, had not yet seen the light of day. That documentation woud have made plain the centrality of Trawniki to the implementation of "Reinhard" and hence Streibel's role in the deaths of 1.5 million Jews between 1941 and 1943. ( )