German interdisciplinary research on the Nazi mass murders since the 1960s started to use the term „mass crimes“ (Massenverbrechen) or „state mass crimes” (staatliche Massenverbrechen) for the extreme violence of Nazism against civilians and POWs.
The term is derived from legal language and was used before that for common crimes with mass character. Several legal professionals (like state prosecutor general Fritz Bauer) and criminologists (esp. Herbert Jäger) used the term to find a more general category for Nazi crimes or German war crimes in WW II. Only in the 1990s some historians started to use the term.
Despite its origins in legal language (and the inherant connotations) the term mass crimes offers certain universal features which are not applicable to similar terms: Mass crimes in this sense are killings on a mass scale ordered and organized by governements or semi-governmental organizations. They include first degree murders (for example on a racist motivation) and man slaughters (for example reprisal killings). Not included are here robbery and forced labor as long as they are not accompanied by extreme violence. It is applicaple especially to extremely violent dictatorships like the Nazi State and the Stalinist State, but also to dictatorships derived from them (like Ustasha Croatia, authoritarian Romania 1941/42 or outer Mongolia). It includes killings specific to the dictatorship like Nazi crimes (Killing of Jews, Roma, Slavic elites and so on) or specifically Stalinist crimes (like killings connected to collectivisation, “Great Terror”, killings of ethnic groups), but also more universal killings, esp. war crimes in the narrow sense (esp. killing of POWs). It avoids the reference to crimes against ethnic groups (genocide) or the more specific features of killing actions like massacres.
On the other hand, it seems to appear more specific than the general term mass violence, which also can be applied to military killings or killings during social upheaval.
The term mass crimes is not yet used very frequently in scholarship and has not yet underwent intensive debate although it was also used by the French scholar Jacques Semelin in a study on the former Yugoslavia.
Herbert Jäger, Makrokriminalität: Studien zur Kriminologie kollektiver Gewalt. Frankfurt am Main: Suhrkamp, 1989.
Herbert Jäger, Verbrechen unter totalitärer Herrschaft: Studien zur nationalsozialistischen Gewaltkriminalität. Olten etc.: Walter, 1967
Dieter Pohl, Verfolgung und Massenmord in der NS-Zeit 1933-1945. Darmstadt: Wissenschaftliche Buchgesellschaft, 2003.
Semelin Jacques, “Analysis of a Mass Crime. The case of the Former Yugoslavia” in Ben Kiernan and Robert Gellately, Specter of genocide : Mass Murders in historical perspective, Cambridge, Cambridge University Press, 2003.