Great answer! I might be able to add a little, in that the jurisdiction, ex post facto law, and illegal kidnapping were all brand new issues in international criminal law (which is still in its infancy) but drawing on international law before and after, in hindsight it generally comports with customary int'l law and current int'l criminal law. This article from 1961 , by an americanized law professor (with credentials from germany and the hague as well) before the trial but after the capture and intention to try him were announced, makes the argument that 1) because Argentina and Isarael had no extradition treaty, and because Eichmann was not an Argentinian citizen, emigrating under a false identity, that Germany would be the proper country to oppose Israel in this (see Nottebohm case )but they in fact supported Israel's efforts 2) couple 1) with Argentina's law forbidding prosecution for events prior to 1945, Argentina is unwilling/ unable to prosecute, thus, despite international law preference that the residence/citizenship country try the accused, another may, under universal jurisdiction when the preferable country is unwilling/unable; and 3) Israel followed US and GB law in the period before its official founding which both allow the disregard of the legality of how someone is brought before their courts, as long the trial is fair once they are present (Baade still concludes if it was Israeli gov agents, the offense against sovereign Argentina may negate all this, but developments in int'l law largely disagree with Baade on this single point).

There are some GB, PCIJ, ICJ, and ICC cases on this, but a recent US one from 1992 emphasizes the effect of an extradition treaty US v Alvarez-Machain and its predecessors (us v caro-quintero, discussed ibid) where US kidnapped drug cartel members from mexico to try them for 1985 torture and murder of US DEA agent, found the defendants had no standing to challenge jurisdiction of US, but bc of extradition treaty and because Mexico protested, they derived standing through the treaty, and caro-quintero was returned to mexico (but with Mexico's consent Alvarez-machain was tried in US).

The Eichmann affair tested these issues and though controversial and on shaky ground at the time, the milosovic and rwandan special courts and others since, have largely ratified how it was handled.

The concern for a 'show trial' was similar to Robert Jackson's concern with 'victor's justice' in his Nuremberg prosecution. He focused on documents and the testimony of the accused themselves (goerhing anyway had a defense similar to eichmann in that 'he carried out lawful orders' and was fairly glib), and only used about 93 witnesses and survivors compared to 3000 or so documents/maps/reports as evidence. Nuremberg has more criticisms than Eichmann (but far less than Tokyo Trials and more recent ones), largely due to Jackson's efforts. Landau should get an awful lot of credit, since Eichmann's trial supplanted Nuremberg as the sort of gold standard in these. Thanks for telling his story. Amazing post.