Witness

In February 1987, a small Native American tribe from California won a landmark ruling at the US Supreme Court granting them the right to conduct gambling activities on their reservation. The campaign by the Cabazon Band of Mission Indians led to the creation of a multi-billion-dollar gaming industry on Indian land across the United States. Simon Watts talks to former Cabazon Band president, Brenda Soulliere, and their lawyer, Glenn Feldman.PHOTO: An Indian-run casino in California (Getty Images)

In the early 1980s deaf children in Nicaragua invented a completely new sign language of their own. It was a remarkable achievement, which allowed experts a unique insight into how human communication develops. Mike Lanchin has been speaking to American linguist Judy Shepard-Kegl, who documented this process and says "our belief is that you are born with a language-ready brain". (Photo credit should read INTI OCON/AFP via Getty Images)

The Empress Dowager Cixi ruled China for 47 years until her death in 1908. But it wasn't until the 1970s that her story began to be properly documented. She'd been vilified as a murderous tyrant, but was that really true or was she a victim of a misogynistic version of history? Prof Sue Fawn Chung was the first academic to go back to study the original documents, and found many surprises. She tells Rebecca Kesby the story of "the much maligned Empress Dowager". (Photo: Chinese Empress Dowager Cixi, portrait c1900. Credit: Ullstein bild/Getty Images)

Norwell Roberts joined the Metropolitan police in 1967. He was put forward as a symbol of progressive policing amid ongoing tensions between the police and ethnic minorities in the capital. But behind the scenes, he endured years of racist abuse from colleagues within the force. Norwell Roberts QPM spoke to Alex Last about growing up in Britain and his determination to be a pioneer in the police force. Photo: London's first black policeman PC Norwell Roberts beginning his training with colleagues at Hendon Police College, London, 5th April 1967. (Hulton Archive/Getty Images)

The treaty which established the European Economic Community was signed by six countries in 1957 - France, West Germany, Belgium, Italy, Luxembourg and the Netherlands. It was hoped that European countries would never go to war again, if they were tied together by economic interests. The treaty formed the basis for what is now the European Union.Photo: European leaders at the Palazzo dei Conservatori in Rome. Credit: Keystone/Getty Images

Madam C. J. Walker was the first ever self-made female millionaire. She was born to former slaves in the USA and was orphaned at seven but against all the odds she went on to create her own business selling black hair-care products. By the time of her death in 1919 she'd become a famous philanthropist and civil rights campaigner. Claire Bowes has been speaking to her great great granddaughter A'Lelia Bundles. Photo: Madam Walker Family Archives/A'Lelia Bundles

The remarkable Turner's oak in Kew Gardens in London not only survived the Great Storm that ravaged the south of England in 1987, but also changed the way that trees are cared for around the world. Alejandra Martins has been speaking to Tony Kirkham, head of the Arboretum at Kew. (Photo: Turner's oak. Credit: Alejandra Martins)

In January 2013 the Indian government began to overhaul the country's laws on rape following the brutal gang rape and killing of a 23 year old physiotherapy student in Delhi. The public outcry across India forced the government to commission a legal review. Farhana Haider has been speaking to Gopal Subramanium, one of the three senior lawyers tasked with reforming the way India tackled violence against women.(Photo: Justice Leila Seth. Justice J Verma and Justice Gopal Subramanium and team deliver their report. January 2013. Credit: Permission of Gopal Subramanium)

Prince Harry and Meghan’s announcement that they will step back from their royal duties is not the first time the British royal family has tried to reform itself from within. In 1992 Queen Elizabeth had what she called her “annus horribilis” . It was the year that her sons Prince Charles and Prince Andrew both separated from their wives, while her daughter Princess Anne got divorced - and it was also the year that Windsor Castle caught fire. The Way Ahead group was set up by senior members of the royal family and some of their closest advisors to make sure that Britain’s monarchy stayed relevant in the modern age. Lucy Burns speaks to Charles Anson, who was the Queen’s press secretary at the time.(Photo: Queen Elizabeth II makes her "annus horribilis" speech at London's Guildhall, November 1992. Credit: Anwar Hussein/Getty Images)

In 1975, San Diego Zoo began placing tissue samples of rare animals in cryogenic storage for the benefit of future generations. Called the Frozen Zoo, the refrigeration system now contains the cells of more than 1000 species ranging from the white rhinoceros to the black-footed ferret. Scientists are now using the collection to try to save species threatened by extinction. Simon Watts talks to Dr Oliver Ryder, who has worked at the Frozen Zoo from the very beginning.PHOTO: Northern White Rhino cells in the Frozen Zoo (San Diego Zoo Institute For Conservation Research)

Whales were being hunted to extinction, when in 1967, a biologist called Dr Roger Payne realised they could sing. It changed the perception of whales and helped found the modern conservation movement. Claire Bowes spoke to Dr Payne about his discovery in 2017. This programme is a rebroadcast.(Photo: Humpback Whale, courtesy of Christian Miller of Ocean Alliance)

Silent Spring, written by marine biologist Rachel Carson, looked at the effect that synthetic pesticides were having on the environment. Within years of its publication in 1962, the widespread use of DDT had been outlawed in the USA. Louise Hidalgo has been speaking to Carson's adopted son Roger Christie about the author and her work.Image: A copy of Silent Spring (Credit: Science Photo Library)

A flightless bird, the dodo became extinct just decades after being discovered on the uninhabited island of Mauritius by European sailors. Because dodos couldn't fly they, and their eggs, were eaten by explorers and the cats and rats that came with them on board their ships. By the late 1600s there were none left. Simon Watts charts the demise and subsequent popularisation of the dodo.Image: An engraving of a dodo. Credit: Science Photo Library.

How scientists discovered that a deadly fungus was killing off amphibians around the world. The chytrid fungus has caused the greatest loss of biodiversity in our time. Alejandra Martins spoke to biologist Dr. Karen Lips, one of the key scientists who unravelled the mystery of the extinctions. Photo: dead frog infected with chytrid fungus. Credit: Forrest Brem

The US tracked down the al Qaeda leader to a city in northern Pakistan in May 2011. Special operations troops were sent to capture or kill bin Laden in a top secret raid in the dead of night. The Americans didn't tell their Pakistani allies about the raid beforehand. Gabriela Jones has been speaking to Nicholas Rasmussen who was in the White House situation room with President Barack Obama and US military chiefs as the raid took place.Photo: Osama bin Laden. Credit:AFP/Getty Images

How a 14-year-old boy became the youngest person to be executed in the USA during the 20th century. George Stinney Jr was sent to the electric chair in 1944. He had been tried for the murder of two young girls, but when the case was reviewed by a court in South Carolina in 2014 his conviction was annulled. Ashley Byrne has been speaking to George Stinney Jr's sister Katherine Robinson, and to Matt Burgess who was one of the team of lawyers who fought to clear his name.Photo: George Stinney Jr in 1944. Credit Alamy.

In January 2014 after decades of violent struggle, a peace deal was agreed in the Philippines between a Muslim separatist organisation and the government. The deal granted largely Muslim areas of the southern Mindanao region greater autonomy in exchange for an end to armed rebellion. Farhana Haider has been speaking to the government's chief negotiator Miriam Coronel-Ferrer about the difficulties posed by being a woman negotiating with a Muslim rebel group.(Photo: MILF peace panel chief Mohagher Iqbal hands over signed documents with Government of the Philippines Peace Panel Chief Negotiator Miriam Coronel Ferrer 27 March, 2014. Credit: Noel Celis/AFP/Getty Images)

Just weeks after the fall of the Berlin Wall East Germans found themselves able to walk into the communist secret police headquarters in Berlin. The much-feared Stasi agents had kept files on millions of their fellow citizens. Soon people were searching the archives. Jim Frank has spoken to Bert Konopatzky who took part in the demonstration which led to the Stasi opening its gates.Photo:East Germans streaming into the secret police headquarters in Berlin on the night of January 15th 1990. Credit: Zöllner/ullstein bild/Getty Images.

The National Trust was founded in 1895, and initially focused on preserving Britain's rural heritage. But their mission expanded in the 1930s to include protecting stately homes - the grand old houses of the British aristocracy - which were under threat. Higher taxation meant many landowners were struggling to maintain their properties while sweeping social changes made it harder for them to find servants. James Lees Milne worked for the National Trust's Country House Scheme, travelling around the country to see which houses the Trust should acquire, and writing a diary about his experiences which paints a vivid picture of a disappearing world of elderly aristocrats living in genteel poverty in crumbling country houses.Lucy Burns presents interviews with James Lees Milne from the BBC archive.(Photo: The National Trust country house Kingston Lacy. Credit: Loop Images/Universal Images Group /Getty Images)

A US Marine's account of the massive US-led assault on the Iraqi city in November 2004. Amid post-invasion chaos in Iraq, the city was seen as a stronghold of insurgents. It was hoped the battle would be a turning point in the fight against the Iraqi insurgency. Alex Last spoke to Colonel Andrew Milburn, author of When The Tempest Gathers, who served as a US military advisor to a frontline Iraqi army unit during the battle.Photo: US Marines of the 1st Battalion 3rd Marines, clear a houses held by insurgents during the battle for Fallujah November 23, 2004,(Photo by Scott Peterson/Getty Images)