By Gideon Long
BBC News, Santiago
Ten years ago, on 16 October, UK police officers marched into a London clinic and arrested Chile's former military leader Augusto Pinochet as he lay convalescing from surgery.
Gen Pinochet died in 2006 without facing trial for human rights abuses
His dramatic detention sent shockwaves around the world, producing both euphoria and condemnation. It is still reverberating today.
Lawyers at Human Rights Watch and at the US-based International Center for Transitional Justice (ICTJ) say it contributed to the establishment in 2002 of the International Criminal Court in The Hague, which has investigated atrocities in Uganda, the Democratic Republic of Congo and Sudan.
In Chile, where Pinochet ruled for 17 years, the knock-on effect of that arrest in London was felt again last year in the decision by the Chilean Supreme Court to extradite the former Peruvian President Alberto Fujimori to Lima to face human rights charges.
"Pinochet's arrest changed the whole conversation about upholding human rights," said Juan Mendez, president of the ICTJ.
"Before it, many of us in the human rights arena were aware of the notion of universal jurisdiction, but we never really thought it would be applicable in our lifetime."
Pinochet was arrested on October 16, 1998.
"If I had been head of state, I would have declared it a public holiday," said Roberto Garreton, a Chilean lawyer who documented hundreds of cases of torture and murder during the general's 1973-1990 rule.
The detention convulsed Chile, where the former general was a senator-for-life and was largely deemed to be above the law.
"In Chile, some of us remember where we were when Kennedy died, but all of us remember where we were when Pinochet was arrested," said Felipe Aguero, programme director of the Ford Foundation in Chile.
Immunity no more
The arrest had a dramatic effect in Chile where, until then, the legacy of the Pinochet era had largely been politely swept under the carpet in favour of reconciliation and the transition to democracy.
Almost overnight, victims of the dictatorship were emboldened to come forward and seek justice, and lawyers were prepared to take on their cases.
Many people in Chile have been calling for truth and justice for years
But the arrest had implications far beyond Chile's borders too. It was important because it was ordered not by a judge in Chile but in Spain.
For the first time, lawyers were using the principle of universal jurisdiction against a former head of state.
Their argument was that the whole world - not just Chile - had an interest in bringing Pinochet to trial.
Although universal jurisdiction had been enshrined in international law since 1948, when it was incorporated into the UN. Convention on Genocide, it had been largely ignored - until Pinochet's arrest.
Suddenly, it seemed, former heads of state no longer enjoyed immunity.
In the end, the general was freed on health grounds and returned to Chile, where he died in 2006 without standing trial.
But even though he was never brought to court, his case opened the door for countless other cross-border prosecutions.
In February 2000, just days before Pinochet returned home, a court in Senegal indicted Chad's former president, Hissene Habre, on torture charges. It was the first time that a former African head of state had been charged with atrocities by the court of another African country.
Mr Habre, sometimes dubbed "Africa's Pinochet", settled in Senegal after he was deposed in 1990.
The case is ongoing.
In the Fujimori case too, Pinochet's arrest set an important precedent. Mr Fujimori, who fled Peru when his government collapsed in 2000, was under house arrest in Chile from 2005 pending an extradition request from Peru.
Everything suggested the Chileans would reject the request and allow him to stay in Chile.
Mr Fujimori waged a long fight to avoid extradition
But in a dramatic ruling, the Supreme Court sent Mr Fujimori back to Lima, where he is now on trial, charged with authorising death squads during the country's crackdown on Maoist guerrillas in the 1990's.
"It's very difficult to imagine that happening without the Pinochet arrest," said Sebastian Brett of Human Rights Watch in Chile.
"The fact that they ordered Fujimori's extradition reflects a significant change within the Chilean judiciary regarding human rights."
However, Juan Mendez of the ICTJ says some governments, particularly in Africa, are now starting to challenge the principle of universal jurisdiction, saying it is being used by the West to target them unfairly, often to punish atrocities committed in times of war or civil unrest.
"You could see that sooner or later there was going to be a backlash to all this and that has indeed happened," Mr Mendez said.
"The real danger is that there is a negative reaction from governments in the Third World and that we lose the ability to bring cases to court."
But Robert Funk, a professor in political science at Chile's Diego Portales University, says that thanks to the Pinochet case the principle of universal jurisdiction is now well established.
It will make, he believes, make some leaders think twice before they step outside the confines of their home countries.
"With Pinochet's arrest it became clear that international law did have jurisdiction and did have some teeth. It instilled the idea that there are some universal principles that the law can address and indeed will address," Professor Funk said.