ITV News US Correspondent Emma Murphy watched the trial and reflects on how the families of those who died "listened to the hell endured by those they love"
Every day of this trial the families of the dead listened to the hell endured by those they love in the final months of their lives.
Most made notes, though the horrific testimony must surely be seared into their minds, alongside the images of orange jump suits and balaclava-clad executioners.
They have endured so much, the years of not knowing, then the years of knowing. For most, knowledge of what became of their missing ones was delivered in execution videos published to the world.
They listened with composure and dignity as others broke down around them. There were moments when a hand would be stretched from one family to another, when their particular tragedy was being detailed.
Other parts of the evidence seemed to harrow the souls of them all. The letters, written from captivity and smuggled out by hostages for whom release was imminent, were glimpses into the relationships so cherished.
“To Poppseed, Mummy and Lauren,” wrote Peter Kassig at the start of his letter. Kayla Mueller’s letter to her parents ended with the words, “with all my everything.” It was as if the air had left the court as they were read.
And yet through it all one man seemed unmoved. El Shafee Elsheikh, with his restyled hair and trimmed beard, listened throughout. He didn’t speak but even his silence exuded arrogance.
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When the former hostages entered the court his eyes followed them to the witness box, it seemed he wished to stare them down. Maybe that worked five years ago when he last saw them as their captor, but now they are the ones with freedom.
He wore a face mask and glasses throughout. In a case where identity was everything, he appeared resistant to removing the mask. In the end it fell to the judge to demand it was was removed, accusing him of using the excuse of Covid-nervousness to frustrate his identification.
El Sheikh is the most high profile IS member to face trial. It took place in the United States because the American government determined that those accused of killing American citizens should be tried on American soil.
El Sheikh will now spend the rest of his life in American custody. The man who once deprived innocent people of their freedom has finally been deprived of his.