Image copyright Baillie Gifford Image caption Philippe Sands has donated his prize money to charity

International lawyer Philippe Sands has won the Baillie Gifford Prize for non-fiction for his book about war crimes.

East West Street: On the Origins of Genocide and Crimes Against Humanity links his own family history with the origins of international law.

The judges called it "a multi-layered history that is impressive in its own right but also a satisfying, suspenseful read".

Sands donated his £30,000 prize money to a refugee charity.

'Trying times'

He told the audience at the prize ceremony in London that he and fellow shortlisted writer Hisham Matar had decided before the announcement that if either were to win, they would share the prize and donate it to an appropriate refugee charity.

"In these trying times we feel that we could all come together to make a real difference," he said.

"From conversations this evening I understand that some of the Baillie Gifford partners would like to match this from their own personal funds, and that Stephanie Flanders will also be donating her honorarium for chairing the prize. My thanks to them all."

Hisham Matar was nominated for his book The Return: Fathers, Sons and the Land in Between.

The other shortlisted books were Svetlana Alexievich's Second-hand Time and Margo Jefferson's Negroland: A Memoir.

Image caption Stephanie Flanders said the winning book was a "stunning achievement"

The Baillie Gifford Prize - formerly the Samuel Johnson Prize - is for the best English-language non-fiction and is open to authors of any nationality.

Former BBC economics editor Stephanie Flanders, chair of the judges, said Sands "had pulled off something extraordinary with this book", adding that it "deserved to reach as wide an audience as possible".

She said: "This is not just one story but several different stories, woven together - each important and each deeply personal to the author. The result is a multi-layered history that is impressive in its own right but also a satisfying, suspenseful read. A stunning achievement."

Sands is Professor of Law at University College London and a practicing barrister. He has been involved in cases at the International Criminal Court and the World Court in The Hague and war crimes trials including Chile's General Pinochet, the Congo, Yugoslavia, Rwanda, Iraq and Guantanamo Bay.

Speaking about his writing he said "as a litigator you are a storyteller".

"East West Street is really a double detective story. It's a search to unlock a family secret: the circumstances in which my grandfather and my grandmother, along with my mother, left Vienna in the course of the years that followed.

"And then it's a detective story about the origins of crimes against humanity and genocide: two subjects that occupy my life as an academic but also as a practising lawyer doing cases in international courts".

Sands has written 16 books including Lawless World, on the Iraq war, and Torture Team, on the Bush administration.

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