A huge collection of materials from journalists in war zones could be used as part of the open-access source for researchers investigating possible crimes against humanity, the head of the world’s largest library has said. The Library of Congress, which officially serves the legislature of the <a href="https://www.thenationalnews.com/tags/us/" target="_blank">US</a> federal government, has dealt with reporters from war-torn countries such as Syria, Librarian of Congress Carla Hayden told <i>The National</i>. “We have these sources and other people can use them in their studies. We don't make judgments,” Ms Hayden said during her visit to the US pavilion at <a href="https://www.thenationalnews.com/tags/expo-2020-dubai/" target="_blank">Expo 2020 Dubai</a>. The expo is held every five years and sees hundreds of countries using pavilions to show off culture, history, folklore and the latest in architecture and technology. Chief among the items on display at the US pavilion is <a href="https://www.thenationalnews.com/uae/expo-2020/2021/10/13/thomas-jeffersons-quran-inspired-us-history-more-than-one-would-think/" target="_blank">a copy of the Quran</a> once owned by former US president Thomas Jefferson. The <a href="https://www.loc.gov/" target="_blank">Library of Congress’s collection</a> is growing at a rate of about two million items a year and reached more than 170 million items in 2020. Its online resources serve a global audience including researchers, politicians, scientists, scholars, artists as well as prosecutors and lawyers. “That means we are a repository that can be referred to over time. It is the world's largest library and half of the collection is in over 170 languages. So it's a national library with a world scope and view,” said Ms Hayden. “For instance, the library has the largest collection of law materials or legal materials in the world, from all over the world.” Ms Hayden was sworn in as the 14th Librarian of Congress in 2016. She is the first woman and the first African-American to lead the national library. She was nominated to the position by former US president Barack Obama. In the midst of the loss of key content removed by social media companies in recent years that could otherwise have been used as evidence available to international prosecutors and investigators, the Library of Congress could play a key role in archiving such materials. “It's not our job to take down materials, but we would collect them. We do collect materials that perhaps were taken down, but they have been collected by, as I mentioned, journalists or experts. Our job, again, is to merely present the sources to any researcher,” Dr Muhannad Salhi, the library’s Arab World Specialist, told <i>The National</i>. “A lot of times journalists approach us, they want their material to be documented. They want future generations to be able to use this material and to document that so they feel that it's in their best interest that this material doesn't get lost.” Social media companies argue that their algorithms promptly remove content that could incite violence and hate speech. They have cracked down, in particular, on extremist content following a live-streamed terror attack in 2019 on Facebook of a gunman killing 51 people at two mosques in Christchurch, New Zealand. But international human rights organisations argue that they have failed to set up mechanisms to ensure that the content they take down is preserved and archived. Some of the deleted videos could have been used in investigating people suspected of committing war crimes. “Social media content, particularly photographs and videos, posted by perpetrators, victims and witnesses to abuses, as well as others, has become increasingly central to some prosecutions of war crimes and other international crimes, including at the International Criminal Court (ICC) and in national proceedings in Europe,” Human Rights Watch said in a recent report. “This content also helps media and civil society document atrocities and other abuses, such as chemical weapons attacks in Syria, a security force crackdown in Sudan, and police abuse in the US.” In 2017, the ICC for the first time issued an arrest warrant against one of Libya’s warlords on suspicions of committing war crimes. It was largely based on Facebook videos shared by activists and journalists.