Between 1941 and 1945, six million Jews were murdered by the Nazi regime. And seven decades later, the few surviving perpetrators and victims of the Holocaust are in their nineties.

Yesterday, 93-year-old Bruno Dey became the latest - and possibly the last - person to be convicted of crimes relating to the darkest period in European history.

Sentencing him to a two-year suspended sentence for accessory to murderThe prosecution did not argue that he personally killed anyone, but that his actions as a tower guard allowed murder to take place., the judge asked, "How could you get used to the horror?"

Dey was 17 when his army unit was stationed at Stutthof concentration camp in occupied Poland. As an SS tower guardThe "Schutzstaffel" (Protection Squad) was a Nazi paramilitary organisation responsible for running the concentration and extermination camps., he was responsible for preventing prisoners from escaping and was, therefore, complicit in their deaths. In total, 65,000 people died in the camp; 4,000 in the gas chambers.

In the nine-month trial, the prosecution proved that 5,232 of these deaths took place on Bruno Dey's watch.

Finding justice for the victims of the Third ReichThe Nazi regime referred to itself as the "Third Empire", following the German Holy Roman Empire (800-1806) and the Second Reich (1871-1918). has been a long and difficult process.

After the war, an international court tried 24 Nazi leaders at the Nuremberg TrialsHeld in the German town of Nuremberg, this was the first time in history that leaders were tried and convicted of crimes against humanity and genocide., but historians believe that a quarter of a million Germans were in some way implicated in genocide. Some fled to South America, like the SS officer Adolf EichmannThe senior Nazi in charge of organising the deportation of Jews to extermination camps during World War Two. He was convicted of crimes against humanity and hanged in 1961., where it took decades to track them down.

But many more, like Bruno Dey, returned to a normal life. Dey married, had two daughters, worked as a baker, and then a truck driver. At the same time, Germany said: "Never forget, never repeat" and coined a new word, "VergangenheitsbewaltigungMeaning "working through the past", the word refers to a cultural movement in Germany to learn from the experience of Nazism. Studying the Holocaust is part of the school curriculum and monuments, memorials and museums have been built to preserve the memory of the atrocities.", to refer to the constant need to remember the Holocaust.

Very few responsible for the genocide were actually tried.

Prosecutors had struggled to prove that specific guards were responsible for specific murders and this grew harder as the years passed, witnesses died, and evidence was lost.

However, in 2011, a former camp guard John Demjanjuk was successfully convicted of accessory to murder. His crime was to be part of the machine - a cog in the "factory of death" - that led thousands to their deaths. That judgement opened the way for more trials and the Nazi-hunters came for Bruno Dey.

But is this fair? As a young private in a brutal regime, Dey arguably had few options. He had the unimaginable choice of the relative safety of guarding Stutthof or facing the Red Army on the eastern front. He claims he did not know the full extent of the horror taking place in the camps and apologised "to those who went through the hell of this madness, as well as to their relatives. Something like this must never happen again".

"I don't want his apology," said camp survivor Marek Dunin-Wasowicz. Judy Meisel was 15 when her mother was murdered. As a tower guard, she said, "[Dey] allowed my mother to be killed. And he was almost successful in helping me get killed as well".

For them, being 17 and following orders is no excuse. And this is their last opportunity to give their testimony in a court of law and see justice carried out.

Yes, say some. This is justice. By bringing Dey to justice, society shows that it will never be acceptable to stand by whilst evil takes place.

Others say no. Far too much time has passed and a 2020 court cannot meaningfully pass judgement on the decisions of a 17-year-old boy in 1944.