The UN said on Wednesday it has taken stock of what the organisation termed Mandela\u2019s \u201cvast legacy for mankind\u201d. UN Secretary-General Ant\u00f3nio Guterres said in his video message for Nelson Mandela International Day: \u201cNelson Mandela was a towering global advocate for justice and equality\u201d. The Day is annually observed on July 18, which was inaugurated by UN General Assembly in November 2009, in recognition of Mandela\u2019s global contribution to the culture of peace and freedom. Mandela, who died in 2013, was the first democratically-elected president of South Africa and the country\u2019s first black head of State, after he had been in prison for 27 years on charges of sabotage before being released and eventually elected president. \u201cHe continues to inspire the world through his example of courage and compassion. Nelson Mandela was held captive for many years. But he never became a prisoner of his past\u201d, Guterres said. The UN chief noted that Mandela poured his energy into reconciliation and his vision of a peaceful, multi-ethnic, democratic South Africa. \u201cRarely has one person in history done so much to stir people\u2019s dreams and move them to action,\u201d the UN chief said adding: \u201cThat struggle for equality, dignity and justice continues.\u201d In December 2015, the General Assembly decided to extend the scope of Nelson Mandela International Day to also promote humane conditions of imprisonment and to encourage societies everywhere to treat prisoners as a continuous part of society by adopting the revised UN Standard Minimum Rules for the Treatment of Prisoners, known as the \u201cNelson Mandela Rules\u201d. The Rules added important safeguards, including an absolute prohibition on torture and ill-treatment and clear restrictions on the use of solitary confinement, instruments of restraint and intrusive searches, as well as detailed guidance on prisoners\u2019 rights to equivalent health-care services. Yury Fedotov, Executive Director of the UN Office on Drugs and Crime (UNODC), said a nation should be judged by how it treats its lowest citizens, not the highest ones. \u201cNelson Mandela spent 27 years in prison in the course of his struggle for justice. He knew better than anyone that \u2018no one truly knows a nation until one has been inside its jails. \u201cA nation should not be judged by how it treats its highest citizens but its lowest ones\u2019\u201d, the UNODC chief said. Fedetov said his office would assist all countries in translating these rules into action, to promote humane conditions of imprisonment and ensure no part of society is forgotten. \u201cNelson Mandela International Day 2018 marks 100 years since the birth of a true hero who left the world a better and more just place than he found it,\u201d Fedotov said.