The jury at an inquest into Princess Diana's death began considering their verdict today after spending almost six months listening to more than 250 witnesses.
"There is no pressure of time. Take as long as is necessary," Lord Justice Scott Baker, the presiding judge, said.
Diana and her lover Dodi al-Fayed died in August 1997 when their Mercedes, driven by chauffeur Henri Paul, crashed in a Paris road tunnel whilst being pursued by paparazzi.
Justice Scott Baker told the jury they could reach one of five possible verdicts at the end of a case that has sparked worldwide interest.
They could decide Diana's death was accidental or opt for unlawful killing through gross negligence either by her chauffeur Henri Paul, by "following vehicles", or by both.
The fifth option, which could give renewed life to the conspiracy theories that have surrounded Diana's death for the past decade, is an open verdict if the 11-member jury find there is insufficient evidence to support any substantive verdict.
The inquest was delayed for 10 years because Britain had to wait for the French legal process and then a British police investigation to run their course before it could begin. Both police inquiries concluded the crash was a tragic accident caused by the chauffeur being drunk and driving too fast.
Under British law, an inquest is needed to determine the cause of death when someone dies unnaturally. Justice Scott Baker specifically instructed the jury not to hand down a verdict that Diana and Dodi died in a staged accident.
Dodi's father, luxury storeowner Mohamed al-Fayed, alleges his son and Diana were killed by British security services on the orders of Prince Philip, Queen Elizabeth's husband and Diana's former father-in-law.
Mr al-Fayed believes her killing was ordered because the royal family did not want the mother of the future king having a child with his son.
He alleges Diana's body was embalmed to cover up evidence she was pregnant. Concluding his three-day summing up, Justice Scott Baker said: "The conspiracy theory advanced by Mohamed al-Fayed has been minutely examined and shown to be without substance."