hilippe Sands, 59, is a professor of law at University College London and a barrister. He appears regularly before the international courts: last year he acted for the prosecution in the Rohingya genocide case at The Hague. His memoir, East West Street, won the 2016 Baillie Gifford prize. His new book, The Ratline, is about an Austrian Nazi, Otto von Wächter, and his wife, Charlotte, who helped him to evade justice when he went on the run in 1945. How is The Ratline connected to East West Street? In 2010 I went to Lviv, in Ukraine, to give a lecture. That led to East West Street. It was supposed to be about my grandfather, Leon, who grew up there, and Hersch Lauterpacht and Rafael Lemkin [also from Lviv], the jurists who put the terms “crimes against humanity” and “genocide” into international law. But then Hans Frank came into it: the governor of German-occupied Poland, who was hanged at Nuremberg. Following a speech he gave in Lviv, the Jews of the region known as Galicia [Lviv was its capital] were exterminated. I came across a book by Frank’s son, Niklas. We met and became friends, and he introduced me to Horst, the son of Otto von Wächter, who was the Nazi governor of Lviv from 1942-1944 and Frank’s deputy. Niklas hates his father; Horst doesn’t. I made a documentary about them, then a podcast about Otto, and now this book. The Ratline is very different from East West Street, isn’t it? The reader is horrified, but also gripped; at times, it’s like a thriller. Yes, and that was the source of bother. I’m really fond of Horst, but he also upsets me [by defending Otto]. I would think: why am I putting myself through this? Then there’s Charlotte. She fascinates me. She’s a Nazi, but what she does for Otto is incredible; there’s something almost beautiful about it. Until May, 1945, he’s pulling all the strings – then, with one snap of a finger, the power balance is changed. He needs her absolutely. How has Horst reacted to The Ratline? He hasn’t read it yet. He’ll be upset. But other Von Wächters have already come out of the woodwork. One begged me not to publish; another asked me to forgive Otto. A book like this is worrying to them in terms of their reputation, particularly in the context of Austria, which has not come to terms with the war as Germany has. They think some things are best not talked about. What’s remarkable is the way that you show Otto in the round. Yes. It’s unhelpful to describe these men as monsters. He did monstrous things, but he was also a father, a lover, a husband, a highly cultured man. One scene that stays with me is in 1942, when the worst killing is going on. At the weekend, he’s going boating. How do you do it? How do you round people up and murder them, then go home and, say, listen to an opera? This is the question, to which there’s no satisfactory answer. Has writing The Ratline brought you closer to understanding where such antisemitism comes from? Otto’s is easier to account for. It comes through his dad, a German nationalist: the idea that in Vienna there are all these Jews from the east coming in. But Charlotte was from a little town. There were only 27 Jews there; her family were magnates, not downtrodden. The Catholic church played a role, and I suspect there was also a deep-seated fear of Bolshevism, which was considered a Jewish idea. Is antisemitism on the rise again? Are there parallels to be made? I don’t think it’s rampant in Britain. It’s there on the far left, and the far right – and plainly, under Jeremy Corbyn, things were allowed to happen in the Labour party that shouldn’t have. But in Europe, there’s no question it is. The tropes in places like Hungary are very clear. Are you frightened? Can it be stopped? I don’t think history repeats itself, but nor does it learn. You get variations on a theme. When the coronavirus crisis is over, nationalism could be rampant. Or we could remember the lessons of the 30s; that the only way out of recession is via global solidarity and trade. Either way, we need to pay attention. Viktor Orbán’s new laws in Hungary are unparalleled in Europe. He can rule open-endedly by decree. Let’s consider our own emergency legislation. Yes, it must be reviewed by parliament in six months. But who would have thought that in 2020 we’d have a situation where people over 70 are told they can’t leave the house? How much of a leap is it from that to: OK, we’re going to place the elderly in “safe areas”? To care-home ghettoes? Four million Jews died in Galicia, including your grandfather’s family, yet when Horst tries to defend his father, you remain so calm, so dispassionate. How did you do it? I do lose my rag with him at one point. My mother-in-law calls it my “elder abuse moment”. I’m a very emotional person. But I strip the emotion out of my sentences. It’s 30 years of training and the practice of the golden rule of not showing your feelings in court. What difference has East West Street, and everything that has followed from that trip to Lviv, made to your life? It has made the past easier. The war was a dark hole that no one talked about. I think it has made my mum’s life easier, too [his mother, Ruth, was carried as a baby to safety in Paris from Vienna in the arms of a stranger whose identity he was able to discover]. Do you know what you’ll write next? Yes, and you couldn’t make it up. There’s a character in The Ratline: a Nazi who escapes to Syria, and then to Chile. He worked for General Pinochet’s interrogation service. The book is about his connection to the events that later catalyse Pinochet’s arrest in London, a case in which I was involved as a lawyer. The Ratline: Love, Lies and Justice on the Trail of a Nazi Fugitive by Philippe Sands is published by Weidenfeld & Nicolson (£20)