It's 75 years on from one of the biggest cases in history - the Nuremberg Trials.
The crime, was Genocide -- the criminals, Nazis -- and the last surviving prosecutor, Benjamin Ferencz is still advocating against conflict and repression.
Now 101-years-old, Ferencz was just a 25-year-old U.S. soldier, when, in the last days of World War Two, he was assigned to collect evidence about the war crimes committed by Germany under Adolf Hitler.
"My job was to get into the concentration camps as they were being liberated, with the dead bodies all over the floor and with people waiting to be burned because the crematorium was so overcrowded. I have seen all that with my own eyes as a war crimes investigator, wearing the uniform of the
United States Army. And I hope the next generation will never have to see anything like that again."
Ferencz became a prosecutor at the U.S. military tribunal in Nuremberg in southern Germany.
He secured the convictions of 22 members of the Einsatzgruppen - the paramilitary death squads who slaughtered upwards of a million, mainly Jewish people, across occupied Europe.
The famous trials are seen to have paved the way for tribunals like the International Criminal Court (ICC) in The Hague, which Ferencz campaigned to be established for decades.
"The defendants murdered over a million people, including hundreds of thousands of children, shot one at a time. That's the world which I grew up in and I hope that the next generation will recognize that that's a horror and should be avoided at all cost. And it means in short, be humans, behave like humans to all other humans, don't behave like wild animals. And if you do that you'll see a more peaceful world than I have seen."
Today the courtroom in Nuremberg has been preserved.
It still draws many visitors hoping to see the seats where Nazis behind some of history’s worst crimes were served their sentences.