What Roeder did was, no doubt, illegal. BUt only because a corrupt set of laws has for far too long protected the practioners of this genocide from the true rule of law. What some German people did in resisting the Nazi holocaust (and they usually died for doing so) was also "illegal"...but in the end that did not protect the perpetratiors of the holocaust from the gallows.
History, and nature's God will ultimately straighten out and right this gross wrong, this gruesome genocide of tens of millions...as another wrong was righted over a four year period in the 1860s, even if that was not the principle reasoning behind that war...it was the emotional and foundational principle that caused the other arguements that led to it. Tragically, this moral evil (which IMHO is even worse) may come to the same kind of end.