Timeline: Justice for Rachel Nickell

1) 1989-1994: String of sex attacks in Mottingham and Plumstead which became known as the Green Chain rapes. One involved a woman who was with her young child.
2) 1992: Murder of Rachel Nickell on Wimbledon Common in front of her two-year-old son.
3) 1993: Murder of Samantha Bissett and her four-year-old daughter Jazmine in Plumstead.

Here are key events surrounding the case of Robert Napper who has pleaded guilty to the killing of Rachel Nickell on Wimbledon Common:

August 1986: Napper stopped and arrested for possession of a loaded air weapon in a public place. Given 12-month conditional discharge.

August 1989: First Green Chain rape. This charge is dropped during the trial in October 1995.

November 1989: Napper's mother, Pauline Lasham, tells police that Napper confessed to a rape in Plumstead Common. Officers fail to find details about that rape because it happened in Plumstead, not on the common. Nothing is done.

March 1992: Attempted rape of second victim. Napper later pleads guilty at the Old Bailey in October 1995. Attempted rape of third victim a week later. Napper admits the offence at the Old Bailey in October 1995.

Killer who slipped through the net

May 1992: Fourth rape. Napper pleads guilty at the Old Bailey in October 1995.

July 1992: Rachel Nickell is killed.

August 1992: Police release E-fit and description of suspect for the rapes. Napper's neighbour tells detectives he matches the description. Officers visit Napper and ask him to provide a blood and saliva sample which he fails to do.

September 1992: A Crimestoppers viewer names Napper as looking like the E-fit. Police return to Napper's house and leave a letter asking him to provide samples for a second time which he ignores again.

Two weeks later Colin Stagg is arrested for the murder of Rachel Nickell.

October 1992: Napper is eliminated from the rape investigation as being too tall, despite one rape victim initially giving his correct height, which she later changed.

Napper is arrested for possession of a firearm and ammunition without a certificate. He is sentenced to eight weeks imprisonment in December 1992.

April 1993: Napper's fingerprints are identified on a tin found in February 1993 buried on Winns Common and containing a handgun. This is not pursued.

August 1993: Colin Stagg is charged with the murder of Rachel Nickell.

November 1993: Samantha and Jazmine Bissett are killed at their Plumstead home.

January 1994: Napper is arrested for shoplifting sweets in Plumstead High Street and given a 12-month conditional discharge.

May 1994: Napper's fingerprints are identified at the Bissett flat. Napper is arrested and charged with the Bissett murders and a DNA sample is taken.

July 1994: Napper is charged with two rapes and two attempted rapes. An internal review of the rape investigations is launched.

September 1994: Colin Stagg is acquitted of the murder of Rachel Nickell. A review of the Rachel Nickell inquiry is launched.

November 1994: Napper is interviewed by Rachel Nickell detectives but he denies involvement and there is no evidence against him.

October 1995: Napper admits the two manslaughters, a rape and two attempted rapes at the Old Bailey. Another rape charge is dropped.

December 1995: Napper is interviewed in prison over Rachel Nickell's death.

October 2001: A review of the Rachel Nickell case is launched.

Napper stabbed Samantha Bissett and smothered her daughter, Jazmine

December 2001: The Forensic Science Service re-examines exhibits but again fails to find any DNA.

January 2002: The Metropolitan Police asks rival firm, LGC Forensics, to work on the review.

July 2004: LGC Forensics find a mixed profile from taping taken off of Rachel's body. The Metropolitan Police assigns a murder squad to the case. The DNA profile is later matched to Napper.

June 2006: Napper is interviewed under caution for five days at Broadmoor Hospital over Rachel Nickell's death but again denies any involvement.

February to October 2007: An independent review of the forensic evidence rules out contamination of samples.

December 2007: Napper is charged with the murder of Rachel Nickell.

December 2008: Napper pleads guilty to killing Rachel Nickell.